10 CSR 40-3.040 - Requirements for Protection of the Hydrologic Balance
PUBLISHER'S NOTE: The secretary of state has determined that the publication of the entire text of the material which is incorporated by reference as a portion of this rule would be unduly cumbersome or expensive. This material as incorporated by reference in this rule shall be maintained by the agency at its headquarters and shall be made available to the public for inspection and copying at no more than the actual cost of reproduction.
This note applies only to the reference material. The entire text of the rule is printed here.
(1) General Requirements.
(A) Surface mining activities shall be
planned and conducted to minimize changes to the prevailing hydrologic balance
in both the mine plan and adjacent areas in order to prevent long-term adverse
changes in that balance that could result from those activities.
(B) Mining and reclamation activities shall
be conducted to prevent material damage to the hydrologic balance outside the
permit area.
(C) Changes in water
quality and quantity, in the depth to groundwater and in the location of
surface water drainage channels shall be minimized so that the approved
post-mining land use of the permit area is not adversely affected.
(D) In no case shall federal and state water
quality statutes, regulations, standards, or effluent limitations be
violated.
(E) Operations shall be
conducted to minimize water pollution and, where necessary, treatment methods
shall be used to control water pollution.
1.
Each person who conducts surface mining activities shall emphasize mining and
reclamation practices that prevent or minimize water pollution. Changes in flow
of drainage shall be used in preference to the use of water treatment
facilities.
2. Acceptable practices
to control and minimize water pollution include, but are not limited to:
A. Stabilizing disturbed areas through land
shaping;
B. Diverting
runoff;
C. Achieving quickly
germinating and growing stands of temporary vegetation;
D. Regulating channel velocity of
water;
E. Lining drainage channels
with rock or vegetation;
F.
Mulching;
G. Selectively placing
and sealing acid- and toxic-forming materials; and
H. Selectively placing waste materials in
backfill areas.
3. If the
practices listed in paragraph (1)(E)2. of this rule are not adequate to meet
the requirements of this chapter, the person who conducts surface mining
activities shall operate and maintain the necessary water treatment facilities
for as long as treatment is required under this chapter.
(2) Water Quality Standards and
Effluent Limitations.
(A) General Limitations.
1. All surface drainage from the disturbed
area, including disturbed areas that have been graded, seeded, or planted,
shall be passed through a siltation structure or a series of siltation
structures before leaving the permit area.
2. Siltation structures and other treatment
facilities shall be maintained until the disturbed area has been restored and
the vegetation requirements of
10 CSR
40-3.120 are met and the quality of the untreated
drainage from the disturbed area meets the applicable state and federal water
quality standards and requirements for the receiving stream.
3. Exemptions may be granted in the permit
and plan from these requirements only when-
A. The disturbed drainage area within the
total disturbed area is small; and
B. The person who conducts the surface mining
activities demonstrates that siltation structures and treatment facilities are
not necessary for drainage from the disturbed drainage areas to meet the
effluent limitations of the applicable state and federal water quality
standards for downstream receiving waters.
4. For the purpose of this section only,
disturbed area shall not include those areas in which only diversion ditches,
siltation structures, or roads are installed in accordance with this chapter
and the upstream area is not otherwise disturbed by the person who conducts the
surface mining activities.
5.
Siltation structures required by this section shall be constructed in
accordance with section (6) of this rule, in appropriate locations before
beginning any surface mining activities in the drainage area to be
affected.
6. Where the siltation
structure or series of siltation structures is used so as to result in the
mixing of drainage from the disturbed areas with drainage from other areas not
disturbed by current surface coal mining and reclamation operations, the
permittee shall achieve the effluent limitations set forth in the following for
all of the mixed drainage when it leaves the permit area.
(B) Discharges of water from areas disturbed
by surface mining activities shall be made in compliance with all applicable
state and federal water quality laws and regulations and with the effluent
limitations for coal mining promulgated by the Missouri Clean Water Commission
set forth in 10 CSR 20-7.015 and promulgated
by the federal government set forth in the Federal Water Pollution Control Act,
P.L.
92-500 , 92nd Congress.
(C) Adequate facilities shall be installed,
operated, and maintained to treat any water discharged from the disturbed area
so that it complies with all federal and state laws, regulations, and
limitations of this section. If the pH of water to be discharged from the
disturbed area is less than 6.0, an automatic lime feeder or other automatic
neutralization process approved in the permit and plan shall be installed,
operated, and maintained. The permit and plan may authorize the use of a manual
system, if it is found that-
1. Flow is
infrequent and presents small and infrequent treatment requirements to meet
applicable standards which do not require use of an automatic neutralization
process; and
2. Timely and
consistent treatment is ensured.
(3) Diversions and Conveyance of Overland
Flow and Shallow Groundwater Flow and Ephemeral Streams. Overland flow,
including flow through litter and shallow groundwater flow from undisturbed
areas, and flow in ephemeral streams, may be diverted away from disturbed areas
by means of temporary or permanent diversions, if required or approved in the
permit and plan as necessary to minimize erosion, to reduce the volume of water
to be treated and to prevent or remove water from contact with acid- or
toxic-forming materials. The following requirements shall be met for all
diversions and for all collection drains that are used to transport water into
water treatment facilities and for all diversions of overland and shallow
groundwater flow and ephemeral streams:
(A)
Temporary diversions shall be constructed to pass safely the peak runoff from a
precipitation event with a two- (2-) year recurrence interval or a larger event
as specified in the permit and plan;
(B) To protect fills and property and to
avoid danger to public health and safety, permanent diversions shall be
constructed to pass safely the peak runoff from a precipitation event with a
ten- (10-) year recurrence interval or a larger event as specified in the
permit and plan. Permanent diversions shall be constructed with gently sloping
banks that are stabilized by vegetation. Asphalt, concrete, or other similar
linings shall be used only when approved in the permit and plan to prevent
seepage or to provide stability;
(C) Diversions shall be designed,
constructed, and maintained in a manner which prevents additional contributions
of suspended solids to streamflow and to runoff outside the permit area, to the
extent possible using the best technology currently available. Appropriate
sediment control measures for these diversions may include, but not be limited
to, maintenance of appropriate gradients, channel lining revegetation,
roughness structures, and detention basins;
(D) No diversion shall be located so as to
increase the potential for landslides. No diversion shall be constructed on
existing landslides, unless approved in the permit and plan;
(E) When no longer needed, each temporary
diversion shall be removed and the affected land regraded, topsoiled, and
revegetated in accordance with 10 CSR 403.030(4) and (5),
10 CSR
40-3.110, and
10 CSR
40-3.120;
(F) Diversion design shall incorporate the
following:
1. Channel lining shall be designed
using standard engineering practices to pass safely the design velocities.
Riprap shall comply with the applicable requirements of
10 CSR
40-3.060(2)(B) 3., except for sand
and gravel;
2. Freeboard shall be
no less than 0.3 feet. Protection shall be provided for transition of flows and
for critical areas such as swales and curves. Where the area protected is a
critical area as determined in the permit and plan, the design freeboard may be
increased;
3. Energy dissipators
shall be installed when necessary at discharge points, where diversions
intersect with natural streams and exit velocity of the diversion ditch flow is
greater than that of the receiving stream;
4. Excess excavated material not necessary
for diversion channel geometry or regrading of the channel shall be disposed of
in accordance with 10 CSR 40-3.060;
5. Topsoil shall be handled in compliance
with 10 CSR
40-3.030; and
6. Diversions shall not be constructed or
operated to divert water into underground mines; and
(G) All diversions shall be designed to
minimize adverse impacts to the hydrologic balance within the permit and
adjacent areas, to prevent material damage outside the permit area and to
assure the safety of the public.
(4) Stream Channel Diversions.
(A) Flow from perennial and intermittent
streams within the permit area may be diverted if the diversions-
1. Are approved in the permit and plan if the
requirements in subsection (18)(A) of this rule are found;
2. Comply with other requirements of this
chapter and 10 CSR 40-4; and
3.
Comply with local, state, and federal statutes and regulations.
(B) When streamflow is allowed to
be diverted, the stream channel diversion shall be designed, constructed, and
removed in accordance with the following:
1.
The longitudinal profile of the stream, the channel, and the floodplain shall
be designed and constructed to remain stable and to prevent, to the extent
possible using the best technology currently available, additional
contributions of suspended solids to streamflow or to runoff outside the permit
area. These contributions shall not be in excess of requirements of state or
federal law. Erosion control structures such as channel lining structures shall
be used in diversions only when approved in the permit and plan as being
necessary to control erosion. These structures shall be approved for permanent
diversions only where they are stable and will require infrequent
maintenance;
2. The combination of
channel, bank, and floodplain configurations shall be adequate to safely pass
the peak runoff of a ten-(10-) year, twenty-four- (24-) hour precipitation
event for temporary diversions, a one hundred- (100-) year, twenty-four- (24-)
hour precipitation event for permanent diversions or larger events required in
the permit and plan. However, the capacity of the channel itself should be at
least equal to the capacity of the unmodified stream channel immediately
upstream and downstream of the diversion; and
3. The design and construction of all stream
channel diversions of perennial and intermittent streams shall be certified by
a qualified registered professional engineer as meeting the performance
standards of this rule and any design criteria set by the director.
(C) When no longer needed to
achieve the purpose for which they were authorized, all temporary stream
channel diversions shall be removed and the affected land regraded and
revegetated, in accordance with 10 CSR 403.030(4) and (5),
10 CSR
40-3.110, and
10 CSR
40-3.120. At the time diversions are removed,
downstream water treatment facilities previously protected by the diversion
shall be modified or removed to prevent overtopping or failure of the
facilities. This requirement shall not relieve the person who conducts the
surface mining activities from maintenance of a water treatment facility
otherwise required under this chapter or the permit.
(D) When permanent diversions are constructed
or stream channels restored, after temporary diversions, the operator shall-
1. Restore, enhance where practicable, or
maintain natural riparian vegetation on the banks of the stream;
2. Establish or restore the stream to its
natural meandering shape of an environmentally acceptable gradient, as
determined in the permit and plan; and
3. Establish or restore the stream to a
longitudinal profile and cross-section, including aquatic habitats (usually a
pattern of riffles, pools and drops rather than uniform depth) that approximate
premining stream channel characteristics.
(5) Sediment Control Measures.
(A) Appropriate sediment control measures
shall be designed, constructed, and maintained using the best technology
currently available to-
1. Prevent, to the
extent possible, additional contributions of sediment to streamflow or to
runoff outside the permit area;
2.
Meet the more stringent of applicable state or federal effluent limitations;
and
3. Minimize erosion to the
extent possible.
(B)
Sediment control measures include practices carried out within, and adjacent
to, the disturbed area. The sedimentation storage capacity of practices in and
downstream from the disturbed area shall reflect the degree to which successful
mining and reclamation techniques are applied to reduce erosion and control
sediment. Sediment control measures consist of the utilization of proper mining
and reclamation methods and sediment control practices, singly or in
combination. Sediment control methods include:
1. Disturbing the smallest practicable area
at any one (1) time during the mining operation through progressive
backfilling, grading and prompt revegetation as required in
10 CSR
40-3.120(1)(B);
2. Stabilizing the backfill material to
promote a reduction in the rate and volume of runoff, in accordance with the
requirements of 10 CSR
40-3.110(1);
3. Retaining sediment within disturbed
areas;
4. Diverting runoff away
from disturbed areas;
5. Diverting
runoff using protected channels or pipes through disturbed areas so as not to
cause additional erosion;
6. Using
straw dikes, riprap, check dams, mulches, vegetative sediment filters, dugout
ponds, and other measures that reduce overland flow velocity, reduce runoff
volume, or trap sediment; and
7.
Treating with chemicals.
(6) Siltation Structures.
(A) General Requirements. Siltation
structures shall be used individually or in series and shall-
1. Be constructed before any disturbance of
the undisturbed area to be drained into the structure;
2. Be located as near as possible to the
disturbed area and out of perennial streams, unless approved in the permit and
plan; and
3. Meet all the criteria
of this section.
(B)
Sediment Storage Volume. Siltation structures shall provide adequate sediment
storage volume.
(C) Detention Time.
Siltation structures shall provide the required theoretical detention time for
the water inflow or runoff entering the pond from a ten- (10-) year,
twenty-four- (24-) hour precipitation event (design event).
(D) Dewatering. The water storage resulting
from inflow shall be removed by a non-clogging dewatering device that has been
designed, constructed, and maintained in accordance with subsection (6)(C) of
this rule or a conduit spillway approved in the permit and plan. The dewatering
device shall not be located at a lower elevation than the maximum elevation of
the sedimentation storage volume.
(E) Each person who conducts surface mining
activities shall design, construct, and maintain siltation structures to
prevent short-circuiting to the extent possible.
(F) The design, construction, and maintenance
of a siltation structure or other sediment control measures in accordance with
this section shall not relieve the person from compliance with applicable
effluent limitations as contained in section (2) of this rule.
(G) There shall be no outflow through the
emergency spillway during the passage of the runoff resulting from the ten-
(10-) year, twenty-four- (24-) hour precipitation event or lesser events
through the siltation structure.
(H) Siltation structures shall be designed,
constructed, and maintained to provide periodic sediment removal sufficient to
maintain adequate volume for the design event.
(I) An appropriate combination of principal
and emergency spillways shall be provided to safely discharge the runoff from a
twenty-five- (25-) year, twenty-four- (24-) hour precipitation event or larger
event required in the permit and plan. The elevation of the crest of the
emergency spillway shall be a minimum of one foot (1') above the crest of the
principal spillway. Emergency spillway grades and allowable velocities shall be
approved in the permit and plan.
(J) The minimum elevation at the top of the
settled embankment shall be one foot (1') above the water surface in the pond
with the emergency spillway flowing at design depth. For embankments subject to
settlement, this one foot (1') minimum elevation requirement shall apply at all
times, including the period after settlement.
(K) The constructed height of the dam shall
be increased a minimum of five percent (5%) over the design height to allow for
settlement, unless it has been demonstrated in the permit and plan that the
material used and the design will ensure against all settlement.
(L) The minimum top width of the embankment
shall not be less than the quotient of (H+35)/5, where H is the height, in
feet, of the embankment as measured from the upstream toe of the
embankment.
(M) The combined
upstream and downstream side slopes of the settled embankment shall not be less
than 1v:5h (20%), with neither slope steeper than 1v:2h (50%). Slopes shall be
designed to be stable in all cases, even if flatter side slopes are
required.
(N) The embankment
foundation area shall be cleared of all organic matter, all surfaces sloped to
no steeper than 1v:1h (100%) and the entire foundation surface
scarified.
(O) The fill material
shall be free of sod, large roots, other large vegetative matter, and frozen
soil, and in no case shall coal-processing waste be used.
(P) The placing and spreading of fill
material shall be started at the lowest part of the foundation. The fill shall
be brought up in horizontal layers of a thickness as is required to facilitate
compaction and meet the design requirements of this section. Compaction shall
be conducted as specified in the design approved in the permit and
plan.
(Q) If a siltation structure
has an embankment that is more than twenty feet (20') in height, as measured
from the upstream toe of the embankment to the crest of the open channel
emergency spillway, unless the emergency spillway is a pipe, where it is
measured to the lowest point in the toe of the embankment, or has both an
embankment that is five feet (5') or more in height, as measured from the
upstream toe of the embankment to the crest of the open channel emergency
spillway and a storage volume of twenty (20) acre-feet or more above the
upstream toe of the embankment, the following additional requirements shall be
met:
1. An appropriate combination of
principal and emergency spillways shall be provided to discharge safely the
runoff resulting from a one hundred- (100-) year, twenty-four- (24-) hour
precipitation event or a larger event required in the permit and
plan;
2. The embankment shall be
designed and constructed with a static safety factor of at least one and
five-tenths (1.5) or a higher safety factor as required in the permit and plan
to ensure stability;
3. Appropriate
barriers shall be provided to control seepage along conduits that extend
through the embankment; and
4. The
criteria of the Mine Safety and Health Administration (MSHA) as published in
30 CFR
77.216 shall be met.
(R) Each structure shall be designed and
inspected during construction under the supervision of, and certified after
construction by, a registered professional engineer.
(S) The entire embankment including the
surrounding areas disturbed by construction shall be stabilized with respect to
erosion by a vegetative cover or other means immediately after the embankment
is completed. The active upstream face of the embankment where water will be
impounded may be riprapped or otherwise stabilized. Areas in which the
vegetation is not successful or where rills and gullies develop shall be
repaired and revegetated in accordance with
10 CSR
40-3.110(6).
(T) Impoundments meeting the Class B or C
criteria for dams in the U.S. Department of Agriculture, Soil Conservation
Service (now renamed as the Natural Resources Conservation Service) Technical
Release No. 60 (210-VI, TR-60, Revised Oct. 1985), entitled "Earth Dams and
Reservoirs," hereafter in these rules referred to as TR-60, or the size or
other criteria of 30 CFR
77.216 must be examined in accordance with
30 CFR
77.216-3. Impoundments which do not meet the
above criteria shall be examined at least quarterly by a qualified person
designated by the operator for the appearance of structural weakness and other
hazardous conditions.
(U) Siltation
structures shall not be removed until removal is authorized and until the
disturbed area has been restored and the vegetation requirements of
10 CSR
40-3.120 are met and the drainage entering the
structure has met the applicable state and federal water quality requirements
for the receiving stream. In no case shall the structure be removed sooner than
two (2) years after the last augmented seeding. When the siltation structure is
removed, the affected land shall be regraded and revegetated in accordance with
10 CSR
40-3.110 and
10 CSR
40-3.120, unless the structure has been approved in
the permit and plan for retention as being compatible with the approved
post-mining land use under
10 CSR
40-3.130. If approved in the permit and plan, the
siltation structure shall meet all the requirements for permanent impoundments
of sections (10) and (17).
(7) Other Treatment Facilities.
(A) Other treatment facilities shall be
designed to treat the ten- (10-) year, twenty-four- (24-) hour precipitation
event unless a lesser design event is approved by the director based on
terrain, climate, other site-specific conditions, and a demonstration by the
operator that the effluent limitations of
30 CFR
816.42 will be met.
(B) Other treatment facilities shall be
designed in accordance with the applicable requirements of section (6) of this
rule.
(8) Discharge
Structures. Discharge from siltation structures, permanent and temporary
impoundments, coal processing waste dams and embankments, and diversions shall
be controlled by energy dissipators, riprap channels, and other devices, where
necessary, to reduce erosion, to prevent deepening or enlargement of stream
channels, and to minimize disturbance of the hydrologic balance. Discharge
structures shall be designed according to standard engineering design
procedures.
(9) Acid- and
Toxic-Forming Materials. Drainage from acid- and toxic-forming materials into
ground and surface water shall be avoided by-
(A) Identifying and burying or treating, or
both, when necessary, materials which may adversely affect water quality or be
detrimental to vegetation or to public health and safety if not buried or
treated, or both;
(B) Preventing
water from coming into contact with acid- and toxic-forming materials in
accordance with 10 CSR
40-3.110(3) and other measures as
required in the permit and plan; and
(C) Burying or otherwise treating all acid-or
toxic-forming materials within thirty (30) days after it is first exposed on
the mine site, or within a lesser period required in the permit and plan.
Temporary storage of the materials may be approved in the permit and plan upon
a finding that burial or treatment within thirty (30) days is not feasible and
will not result in any materials risk of water pollution or other environmental
damage. Storage shall be limited to the period until burial or treatment, or
both, first becomes feasible. Acid-or toxic-forming materials to be stored
shall be placed on impermeable material and protected from erosion and contact
with surface water.
(10)
Permanent and Temporary Impoundment.
(A)
Impoundments meeting the criteria of
30 CFR
77.216(a) shall comply with
the requirements of 30 CFR
77.216 and this section. The plan required to
be submitted to the district manager of the MSHA under
30 CFR
77.216 shall also be submitted to the
director as part of the permit application. Furthermore, impoundments meeting
the Class B or C criteria for dams in TR-60 shall comply with the "Minimum
Emergency Spillway Hydrologic Criteria" table in TR-60 and the requirements of
this section.
(B) Permanent
impoundments are prohibited unless authorized in the permit and plan upon the
basis of the following demonstration:
1. The
quality of the impounded water shall be suitable on a permanent basis for its
intended use and discharge of water from the impoundment shall not degrade the
quality of receiving waters to less than the water quality standards
established pursuant to applicable state and federal laws;
2. The level of water shall be sufficiently
stable to support the intended use;
3. Adequate safety and access to the
impounded water shall be provided for proposed water users;
4. Water impoundments shall not result in the
diminution of the quality or quantity of water used by adjacent or surrounding
landowners for agricultural, industrial, recreational, or domestic
uses;
5. The design, construction,
and maintenance of structures shall achieve the minimum design requirements
applicable to structures constructed and maintained under the Watershed
Protection and Flood Prevention Act,
P. L.
83-566 (U.S.C. 1006). Requirements for
impoundments that meet the size or other criteria of the MSHA,
30 CFR
77.216(a) are contained in
United States Soil Conservation Service Technical Release No. 60, Earth
Dams and Reservoirs, July 2005, incorporated by reference and
published by the USDA, NRCS, Office of the Chief, 1400 Independence Ave., SW,
Room 5105-A, Washington, DC 20250. This rule does not incorporate any later
amendments or additions to this incorporated material. Requirements for
impoundments that do not meet the size or other criteria contained in
30 CFR
77.216(a) are contained in
United States Natural Resources Conservation Service, Conservation Practice
Standard, POND, No. CODE 378, January 2004, incorporated by reference and
published by the Missouri NRCS State Office, Parkade Center, Suite 250, 601
Business Loop 70 West, Columbia, MO 65203-2546. This rule does not incorporate
any later amendments or additions to this incorporated material;
6. The size of the impoundment is adequate
for its intended purposes; and
7.
The impoundment will be suitable for the approved post-mining land
use.
(C) Temporary
impoundments of water in which the water is impounded by a dam shall meet the
requirements of subsections (6)(F)- (V) of this rule.
(D) Excavations that will impound water
during or after the mining operation shall have perimeter slopes that are
stable and shall not be steeper than 1v:2h (50%). Where surface runoff enters
the impoundment area, the side slope shall be protected against
erosion.
(E) Slope protection shall
be provided to minimize surface erosion at the site and protect against sudden
drawdown. Sediment control measures shall be required where necessary to reduce
the sediment leaving the site.
(F)
All embankments of temporary and permanent impoundments and the surrounding
areas and diversion ditches disturbed or created by construction, shall be
graded, fertilized, seeded, and mulched to comply with the requirements of
10 CSR
40-3.120 immediately after the embankment is
completed, provided that the active, upstream face of the embankment where
water will be impounded may be riprapped or otherwise stabilized. Areas in
which the vegetation is not successful or where rills and gullies develop shall
be repaired and revegetated to comply with the requirements of
10 CSR
40-3.110(6) and
10 CSR
40-3.120.
(G) All dams and embankments shall be
routinely inspected by a qualified registered professional engineer or by
someone under the supervision of a qualified registered professional engineer.
The professional engineer or specialist shall be experienced in the design and
construction of impoundments. Inspections shall be made regularly during
construction, upon completion of construction and at least yearly until removal
of the structure or release of the performance bond.
(H) All dams and embankments shall be
routinely maintained during the mining operations. Vegetative growth shall be
cut where necessary to facilitate inspection and repairs. Ditches and spillways
shall be cleaned. Any combustible material present on the surface, other than
material such as mulch or dry vegetation used for surface stability, shall be
removed and all other appropriate maintenance procedures followed.
(I) All dams and embankments subject to 10
CSR 40 shall be certified by a qualified registered professional engineer
during construction immediately after construction and annually after that as
having been constructed, maintained, or both, to comply with the requirements
of 10 CSR 40. All coal-processing waste dams and embankments covered by
10 CSR
40-3.080(9)-(11) shall be certified
by a qualified registered professional engineer. Certification reports shall be
provided certifying that the impoundment has been constructed and maintained as
designed and in accordance with the approved plan and this chapter, shall
include a discussion on any appearance of instability, structural weakness, or
other hazardous condition and shall include statements on:
1. Existing and required monitoring
procedures and instrumentation;
2.
The design depth and elevation of any impounded waters at the time of the
initial certification report or the average and maximum depth and elevations of
any impounded waters over the past year for the annual certification
reports;
3. Existing storage
capacity of the dam or embankment;
4. Any fires occurring in the construction
material up to the date of the initial certification or over the past year for
the annual certification reports; and
5. Any other aspects of the dam or embankment
affecting stability, including structural weakness, erosion, and other
hazardous conditions.
(J)
If any examination or inspection discloses that a potential hazard exists, the
person who examined the impoundment shall promptly inform the director of the
finding and of the emergency procedures formulated for public protection and
remedial action. If adequate procedures cannot be formulated or implemented,
the director shall be notified immediately. The director shall then notify the
appropriate agencies that other emergency procedures are required to protect
the public.
(K) Plans for any
enlargement, reduction in size, reconstruction, or other modification of dams
or impoundments shall be submitted to the director and shall comply with the
requirements of this section. Except where a modification is required to
eliminate an emergency condition constituting a hazard to public health,
safety, or the environment, the plans will be approved before modification
begins.
(L) Stability.
1. An impoundment meeting the Class B or C
criteria for dams in TR-60, or the size or other criteria of
30 CFR
77.216(a) shall have a
minimum static safety factor of 1.5 for a normal pool with steady state seepage
saturation conditions, and a seismic safety factor of at least 1.2.
2. Impoundments not included in paragraph
40-3.040(10)(L)1. of this section, except for a coal mine waste impounding
structure, shall have a minimum static safety factor of 1.3 for a normal pool
with steady state seepage saturation conditions or meet the requirements of
Natural Resources Conservation Service, Conservation Practice Standard, POND
No. CODE 378, December 1998, and be less that twenty feet (20') feet in
height.
(M) Freeboard.
Impoundments shall have adequate freeboard to resist overtopping by waves and
by sudden increases in storage volume. Impoundments meeting the Class B or C
criteria for dams in TR-60 shall comply with the freeboard hydrograph criteria
in the "Minimum Emergency Spillway Hydrologic Criteria" table in
TR-60.
(N) Foundation.
1. Foundations and abutments for an
impounding structure shall be stable during all phases of construction and
operation and shall be designed based on adequate and accurate information on
the foundation conditions. For an impoundment meeting the Class B or C criteria
for dams in TR-60, or the size or other criteria of
30 CFR
77.216(a), foundation
investigation, as well as any necessary laboratory testing of foundation
material, shall be performed to determine the design requirements for
foundation stability.
2. All
vegetative and organic materials shall be removed and foundations excavated and
prepared to resist failure. Cutoff trenches shall be installed if necessary to
ensure stability.
(O)
Spillways. An impoundment shall have either a combination of principal and
emergency spillways, a single spillway configured as specified in
10 CSR
40-3.040(10)(O) 1. of this section,
or no spillways as specified in
10 CSR
40-3.040(10)(O) 3. of this section.
The impoundment shall be designed and constructed to safely pass or contain the
applicable design precipitation event specified in
10 CSR
40-3.040(10)(O) 2. or 3. of this
section.
1. A single open-channel spillway
can be utilized if it is-
A. Of nonerodible
construction and designed to carry sustained flows; or
B. Earth- or grass-lined and designed to
carry short-term, infrequent flows at non-erosive velocities where sustained
flows are not expected.
2. Except as specified in
10 CSR
40-3.040(10)(O) 3. of this section,
the required design precipitation event for an impoundment meeting the spillway
requirements of 10 CSR
40-3.040(10)(O) of this section is-
A. For an impoundment meeting the Class B or
C criteria for dams in TR-60, the emergency spillway hydrograph criteria in the
"Minimum Emergency Spillway Hydrologic Criteria" table in TR-60;
B. For an impoundment meeting or exceeding
the size or other criteria of
30 CFR
77.216(a), a one hundred-
(100-) year twenty-four- (24-) hour event or greater as specified by the
director or commission; or
C. For
an impoundment not included in
10 CSR
40-3.040(10)(O) 2.A. and B. of this
section, as specified in Table 3 of the Natural Resources Conservation Service,
Conservation Practice Standard, POND, No. CODE 378, December 1998.
3. A temporary impoundment that
relies solely on storage capacity to control the runoff from the design
precipitation event may be utilized with no spillway when it is demonstrated by
the operator and certified by a qualified registered professional engineer that
the impoundment will safely contain the design precipitation event, and that
the stored water will be safely removed in accordance with current, prudent,
engineering practices. Such an impoundment must be located where failure would
not be expected to cause loss of life or serious property damage.
A. Impoundments meeting the Natural Resources
Conservation Service Class B or C criteria for dams in TR-60, or the size or
other criteria of 30 CFR
77.216(a) shall be designed
to safely contain the runoff of the probable maximum precipitation (PMP) of a
six- (6-) hour event.
B.
Impoundments not included in subparagraph
10 CSR
40-3.040(10)(O) 3.A. of this section
shall be designed to control the precipitation of the one hundred- (100-) year
twenty-four- (24-) hour event.
(11) Groundwater Protection.
(A) Backfilled materials shall be placed so
as to minimize contamination of groundwater systems with acid, toxic, or
otherwise harmful mine drainage to minimize adverse effects of mining on
groundwater systems outside the permit area, and to support approved
post-mining land uses.
(B) To
control the effects of mine drainage, pits, cuts, and other mine excavation or
disturbances shall be located, designed, constructed, and utilized in a manner
as to prevent or control discharge of acid, toxic, or otherwise harmful mine
drainage waters into groundwater systems and to prevent adverse impacts on
these groundwater systems or on approved post-mining land
uses.
(12) Protection of
Groundwater Recharge Capacity. Surface mining activities shall be conducted in
a manner that facilitates reclamation which will restore approximate premining
recharge capacity through restoration of the capability of the reclaimed areas
as a whole, excluding coal-processing waste and underground development waste
disposal areas and fills, to transmit water to the groundwater system. The
recharge capacity shall be restored to a condition which-
(A) Supports the approved post-mining land
use;
(B) Minimizes disturbances to
the prevailing hydrologic balance in the mine plan area and in adjacent areas;
and
(C) Provides a rate of recharge
that approximates the premining recharge rate.
(13) Surface Water and Groundwater
Monitoring.
(A) Groundwater.
1. Groundwater levels, infiltration rates,
subsurface flow and storage characteristics, and the quality of groundwater
shall be monitored in a manner approved in the permit and plan, to determine
the effects of surface mining activities on the recharge capacity of reclaimed
lands and on the quantity and quality of water in groundwater systems in the
mine plan and adjacent areas.
A. Groundwater
monitoring data shall be submitted every three (3) months to the director or
more frequently as prescribed by the director. Monitoring reports shall include
analytical results from each sample taken during the reporting period. When the
analysis of any groundwater sample indicates noncompliance with the permit
conditions, the operator shall promptly notify the director and take remedial
measures provided for in
10 CSR
40-6.050(9) and
10 CSR
40-6.070(14).
B. Groundwater monitoring shall proceed
through mining and continue during reclamation until bond release. Consistent
with the procedures of
10 CSR
40-6.090, the director may modify the monitoring
requirements, including the parameters covered and the sampling frequency, if
the operator demonstrates, using the monitoring data obtained under this
paragraph, that-
(I) The operation has
minimized disturbance to the prevailing hydrologic balance in the permit and
adjacent areas and prevented material damage to the hydrologic balance outside
the permit area; water quantity and quality are suitable to support approved
post-mining land uses and the water rights of other users have been protected
or replaced; or
(II) Monitoring is
no longer necessary to achieve the purposes set forth in the monitoring plan
approved under 10 CSR
40-6.050(9)(C).
2. When surface mining activities may affect
the groundwater systems serving as aquifers which significantly ensure the
hydrologic balance of water use on or off the mine plan area, groundwater
levels and groundwater quality shall be periodically monitored. Monitoring
shall include measurements from a sufficient number of wells and mineralogical
and chemical analyses of aquifer, overburden, and spoil that are adequate to
reflect changes in groundwater quantity and quality resulting from those
activities. Monitoring shall be adequate to plan for modification of surface
mining activities, if necessary, to minimize disturbance of the prevailing
hydrologic balance.
3. As specified
and approved in the permit and plan, the person who conducts surface mining
activities shall conduct additional hydrologic tests, including drilling,
infiltration tests, and aquifer tests and shall submit the results to the
director, to demonstrate compliance with sections (11)-(13) of this
rule.
(B) Surface Water.
1. Surface water monitoring shall be
conducted in accordance with the monitoring program submitted under
10 CSR
40-6.050(9)(C) 4. and approved in the
permit and plan. The permit and plan shall set forth the nature of data,
frequency of collection, and reporting requirements. Monitoring shall-
A. Be adequate to accurately measure and
record water quantity and quality of the discharges from the permit
area;
B. Be reported when
analytical results of the sample collections indicate noncompliance with a
permit condition or applicable standard; the person who conducts the surface
mining activities shall notify the director within five (5) days. Where a
National Pollutant Discharge Elimination System (NPDES) permit effluent
limitation noncompliance has occurred, the person who conducts surface mining
activities shall forward the analytic results concurrently with the written
notice of noncompliance; and
C.
Result in quarterly reports to the director, to include analytical results from
each sample taken during the quarter. Any sample results which indicate a
permit violation will be immediately reported to the director as provided for
in 10 CSR
40-6.050(9) and
10 CSR
40-6.120(5). In those cases where the
discharge for which water monitoring reports are required is also subject to
regulation by an NPDES permit issued under the Clean Water Act of 1977
(30 U.S.C. Sections
1251 -1378 ) and where the permit includes
provisions for equivalent reporting requirements and requires filing of water
monitoring reports within ninety (90) days or less of sample collection, the
following alternative procedure shall be used. The person who conducts the
surface mining activities shall submit to the director on the same time
schedule as required by the NPDES permit or within ninety (90) days following
sample collection, whichever is earlier, either:
(I) A copy of the completed reporting form
filed to meet NPDES permit requirements; or
(II) A letter identifying the state or
federal government official with whom the reporting form was filed to meet
NPDES permit requirements and the date of filing.
2. After disturbed areas have been
regraded and stabilized according to this chapter, the person who conducts
surface mining activities shall monitor surface water flow and quality. Data
from this monitoring may be used to demonstrate that the quality and quantity
of runoff without treatment is consistent with the requirements of this chapter
to minimize disturbance to the prevailing hydrologic balance and to attain the
approved post-mining land use. These data may also provide a basis for approval
by the commission or director for removal of water quality or flow control
systems.
3. Equipment, structures
and other devices necessary to accurately measure and sample the quality and
quantity of surface water discharges from the disturbed area shall be properly
installed, maintained, and operated and shall be removed when no longer
required.
(14)
Transfer of Wells.
(A) An exploratory or
monitoring well may only be transferred by the person who conducts surface
mining activities for further use as a water well with the prior approval of
the commission or director. That person and the surface owner of the lands
where the well is located shall jointly submit a written request to the
director for that approval.
(B)
Upon an approved transfer of a well, the transferee shall-
1. Assume primary liability for damages to
persons or property from the well;
2. Plug the well when necessary, but in no
case later than abandonment of the well; and
3. Assume primary responsibility for
compliance with 10 CSR 40-3.020 and those of the
Wellhead Protection Section, Division of Geology and Land Survey, at 10 CSR 23
Chapter 3 with respect to the well.
(C) Upon an approved transfer of a well, the
transferor shall be secondarily liable for the transferee's obligations under
subsection (13)(B) of this rule, until release of the bond or other equivalent
guarantee required by 10 CSR 40-7 for the area in which the well is
located.
(15) Water
Rights and Replacement. Any person who conducts surface mining activities shall
replace the water supply of an owner of interest in real property who obtains
all or part of his/her supply of water for domestic, agricultural, industrial,
or other legitimate use from an underground or surface source, where the water
supply has been affected by contamination, diminution, or interruption
proximately resulting from the surface mining activities.
(16) Discharge of Water into an Underground
Mine. Surface water shall not be diverted or otherwise discharged into
underground mine workings, unless allowed by section
577.155, RSMo, and the person
who conducts the surface mining activities demonstrates in the permit and plan
application that this will-
(A) Abate water
pollution or otherwise eliminate public hazards resulting from surface mining
activities;
(B) Be discharged as a
controlled flow, meeting the effluent limitations of section (2) of this rule
for pH and total suspended solids;
(C) Not cause, result in, or contribute to,
in any event, a violation of applicable water quality standards or effluent
limitations by discharging water from underground mines to surface
waters;
(D) Minimize disturbance to
the hydrologic balance; and
(E)
Meet the approval of the MSHA.
(17) Post-mining Rehabilitation of Siltation
Structures, Diversions, Impoundments, and Treatment Facilities. Before
abandoning the permit area, the person who conducts the surface mining
activities shall renovate all permanent siltation structures, diversions,
impoundments, and treatment facilities to meet criteria specified in the
detailed design plan for the permanent structures and impoundments.
(18) Stream Buffer Zones.
(A) No land within one hundred feet (100') of
a perennial stream or an intermittent stream shall be disturbed by surface
mining activities, unless the director specifically authorizes surface mining
activities closer to, or through, a perennial stream. The director may
authorize these activities only upon finding that-
1. Surface mining activities will not cause
or contribute suspended solids to stream flow or runoff outside the permit area
in excess of the requirements established by the Missouri Clean Water
Commission, Department of Natural Resources, set forth in
10 CSR
20-7.015 and promulgated by the federal government set
forth in the Federal Water Pollution Control Act
P.L.
92-500 and all modifications to these laws and
regulations;
2. Surface mining
activities will not adversely affect the water quantity and quality or other
environmental resources of the stream; and
3. If there will be a temporary or permanent
stream channel diversion, it will comply with section (4).
(B) The area not to be disturbed shall be
designated as a buffer zone, and the operator shall mark it as specified in 10
CSR 403.010.
Notes
State regulations are updated quarterly; we currently have two versions available. Below is a comparison between our most recent version and the prior quarterly release. More comparison features will be added as we have more versions to compare.
No prior version found.