Current through Register Vol. 50, No. 9, March 1, 2024
RELATES TO:
KRS
350.085,
350.100,
350.151,
350.405,
350.420,
350.465
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 design and construction of temporary and permanent
diversions of overland flow, shallow groundwater flow, ephemeral streams, and
intermittent and perennial streams.
Section
1. General Requirements.
(1)
Surface flow from mined areas abandoned before May 3, 1978 and any flow from
undisturbed or reclaimed areas, after meeting the criteria of
405 KAR
18:070 and
405 KAR
18:090 for siltation structure removal, may be
diverted around the disturbed area and water treatment facilities by means of
temporary or permanent diversions.
(2) Diversions shall not be constructed or
operated to divert water into underground mines without the approval of the
cabinet under
405 KAR
18:060, Section 9.
(3) The design, construction, and maintenance
of diversion ditches shall insure public health and safety, protect property,
be stable, minimize adverse impacts to the hydrologic balance, and prevent
additional contributions of suspended solids to stream flow and to run off
outside the permit area to the extent possible using the best technology
currently available. The following criteria are to be incorporated in the
design and construction of a diversion ditch:
(a) Freeboard shall be no less than
three-tenths (0.3) foot. 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 by the cabinet, the cabinet may require that the
design freeboard be increased.
(b)
Excess excavated material not necessary for diversion channel geometry or
regrading of the channel shall be disposed of in accordance with
405 KAR
18:130 and
405 KAR
18:190.
(c) Topsoil shall be handled in compliance
with
405 KAR 18:050.
(d) Channel protection shall be used to
prevent erosion of the ditch. The following criteria shall be used unless the
cabinet specifies otherwise:
1. Except when
located in solid rock or when riprap or other nonerodible, nondegradable
materials are used, diversion ditches are to be fertilized, seeded, and mulched
to comply with the requirements of
405 KAR 18:200 after
the ditch is constructed.
2. Riprap
or other nonerodible, nondegradable materials shall be used when a diversion
ditch is not located in solid rock or the design velocity is five (5) feet per
second or greater for the peak discharge used in the design of the ditch.
Material used shall be free of acid-forming material and toxic-forming material
and riprap shall comply with the durability requirements of
405 KAR
18:130, Section 1(6)(c)2, except that sand and gravel
shall not be used.
(e)
Side slopes shall be no steeper than 1h:4v for solid rock, 1h:1v for riprap
lined, and 2h:1v for grass protected ditches.
(f) Diversion ditch design capacity shall
comply with the provisions of this paragraph, except where a larger capacity is
required by other administrative regulations of 405 KAR Chapters 7 through 24
for specific types of diversions or where a larger capacity is required by the
cabinet.
1. The channel of any diversion ditch
which diverts run-off around a sediment control structure, water treatment
facility, or impoundment, excluding dugout structures, shall be adequate to
pass the peak discharge from the design storm for the hydraulic capacity of the
sediment control structure, water treatment facility, or impoundment (i.e. if
the impoundment is designed to pass the 100 year, twenty-four (24) hour storm
event so shall the ditch). This size requirement shall not apply if the
hydraulic capacity of the sediment control structure, water treatment facility,
or impoundment takes into account the entire area contributing drainage, as
though the bypass diversion ditch did not exist.
2. The channel of any diversion ditch which
diverts run-off to a sediment control structure or water treatment facility
shall be adequate, at a minimum, to pass the peak discharge of a ten (10) year,
twenty-four (24) hour storm event.
3. The channel, bank, and flood plain
configuration of any diversion ditch, which diverts a perennial or intermittent
stream, shall be adequate to pass the peak discharge of a ten (10) year,
twenty-four (24) hour storm event for temporary ditches and the 100 year,
twenty-four (24) hour event for permanent ditches. However, the capacity of the
channel itself shall be equal to or greater than the capacity of the unmodified
stream channel immediately upstream and downstream of the diversion.
4. The channel of any other diversion ditch
which diverts ephemeral streams or overland flow shall be adequate to pass the
peak discharge of the two (2) year, twenty-four (24) hour storm for temporary
ditches and the ten (10) year, twenty-four (24) hour storm for permanent
ditches.
(4)
No diversion shall be located so as to increase the potential for land slides.
No diversion shall be constructed on existing land slides, unless approved by
the cabinet.
(5) Diversions of
perennial streams and intermittent streams shall be designed and certified by a
registered professional engineer and after construction shall be inspected and
certified by the responsible registered professional engineer as having been
constructed in accordance with the approved design plans. The certifications
required by this subsection shall be made pursuant to
405 KAR
7:040, Section 10.
(6) Diversion ditches shall be maintained to
pass their respective design storms.
(7)
(a)
When no longer needed to achieve the purpose for which they were authorized,
all temporary diversions shall be removed and the affected land regraded and
revegetated, in accordance with
405 KAR 18:050, Sections
4 and 5;
405 KAR
18:190; and
405 KAR 18:200. 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 permittee from maintenance of a water treatment facility otherwise required
under 405 KAR or the permit.
(b)
Each ephemeral stream channel affected by surface coal mining and reclamation
operations shall be reclaimed or permanently diverted in a channel designed and
constructed so as to restore or approximate the premining characteristics of
the original stream channel (including natural riparian vegetation) to promote
the recovery and enhancement of the aquatic habitats, except for situations in
which a reach of a stream channel cannot be restored to such characteristics
because of the existence of an excess spoil fill, permanent stream-crossing,
permanent impoundment, or coal mine waste disposal area constructed in
accordance with
405 KAR
18:100,
405 KAR
18:130,
405 KAR
18:140,
405 KAR
18:160, and
405 KAR 18:230 as
applicable.
Section
2. Diversions of Perennial and Intermittent Streams.
(1) Flow from perennial and intermittent
streams within the permit area may be diverted, if the diversions:
(a) Are approved by the cabinet after making
the findings called for in
405 KAR
18:060, Section 11;
(b) Comply with other requirements of 405 KAR
Chapters 7 through 24; and
(c)
Comply with applicable local, state, and federal statutes and
regulations.
(2) When
permanent diversions are constructed or stream channels restored, after
temporary divisions, the permittee shall:
(a)
Restore, enhance where practicable, or maintain natural riparian vegetation on
the banks of the stream;
(b)
Establish or restore the stream to an environmentally acceptable alignment, as
determined by the cabinet;
(c)
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; and
(d) Comply
with
405
KAR 18:180.
(3) Where the cabinet approves the placement
of a coal refuse pile, coal waste impoundment, or an excess spoil fill in an
intermittent or perennial stream under
405 KAR
18:060, Section 11, and it is not practicable to
comply with subsection (2) of this section, then the diversion of the stream
channel shall comply with the requirements for diversions set forth in the
performance standards for those structures.
Section 3. Applicability of Amendments to
this Administrative Regulation.
(1) Except as
provided in subsection (2) of this section, the amendments to this
administrative regulation that became effective on February 4, 1986 shall apply
to permits issued on or after July 1, 1986. Permittees conducting surface coal
mining and reclamation operations under permits issued before that date shall
comply with the requirements which preceded the 1986 amendments, the approved
permit application and the conditions of permit issuance.
(2) The provisions of Section 1(3)(f)1 shall
apply on and after May 5, 1986 to each surface coal mining and reclamation
operation which includes an impoundment classified, pursuant to
405 KAR
7:040, Section 5, as a (B) or (C) structure. Permits
issued before that date shall be revised as necessary.
STATUTORY AUTHORITY: KRS Chapter 13A, 350.028, 350.100,
350.151, 350.420, 350.465