Current through Register Vol. 35, No. 18, September 24, 2024
A. General. Each
application shall include a general plan for each proposed sedimentation pond,
water impoundment, and coal processing waste bank, dam, or embankment within
the proposed permit area.
(1) Each general
plan shall:
(a) be prepared by, or under the
direction of, and certified by a registered professional engineer, with
assistance from experts in related fields such as land surveying, reclamation
or mined land rehabilitation;
(b)
contain a description, map, and cross section of the structure and its
location;
(c) contain preliminary
hydrologic and geologic information required to assess the hydrologic impact of
the structure;
(d) contain a survey
describing the potential effect on the structure from subsidence of the
subsurface strata resulting from past underground mining operations if
underground mining has occurred; and
(e) contain a certification statement which
includes a schedule setting forth the dates that any detailed design plans for
structures that are not submitted with the general plan will be submitted to
the director; the director shall have approved, in writing, the detailed design
plan for a structure before construction of the structure begins.
(2) Each detailed design plan for
a structure that meets the U.S. natural resources conservation service class B
or C criteria for dams in NRCS technical release No. 60 (210-VI-TR60, Oct.
1985), "earth dams and reservoirs", or meets or exceeds the size or other
criteria of the mine safety and health administration,
30
CFR 77.216(a) shall:
(a) be prepared by, or under the direction
of, and certified by a qualified registered professional engineer with
assistance from experts in related fields such as geology, land surveying,
reclamation or mined land rehabilitation;
(b) include any geotechnical investigation,
design, and construction requirements for the structure;
(c) describe the operation and maintenance
requirements for each structure; and
(d) describe the timetable and plans to
remove each structure, if appropriate.
(3) Each detailed design plan for a structure
that does not equal or exceed the size or other criteria in Paragraph (2) of
Subsection A of 19.8.9.909 NMAC shall:
(a) be
prepared by, or under the direction of, and certified by a qualified registered
professional engineer or registered land surveyor except that all coal
processing waste dams and embankments covered by 19.8.20.2047 through 2049 NMAC
shall be certified by qualified registered professional engineer;
(b) include any design and construction
requirements for the structure, including any required geotechnical
information;
(c) describe the
operation and maintenance requirements for each structure; and
(d) describe the timetable and plans to
remove each structure, if appropriate.
B. Sedimentation ponds. Sedimentation ponds,
whether temporary or permanent, shall be designed in compliance with the
requirements of 19.8.20.2014 NMAC. Any sedimentation pond or earthen structure
which will remain on the proposed permit area as a permanent water impoundment
shall also be designed to comply with the requirements of 19.8.20.2017 NMAC.
Each plan shall, at a minimum, comply with the requirements of the mine safety
and health administration,
30
CFR 77.216-1 and
77.216-2,
and the state engineer and shall be submitted to the director as part of the
permit application.
C. For
impoundments not included in Paragraph (2) of Subsection A of 19.8.9.909 NMAC,
the director may establish through the state program approval process,
engineering design standards that ensure stability comparable to a 1.3 minimum
static safety factor in lieu of engineering tests to establish compliance with
the minimum static safety factor of 1.3 specified in Paragraph (3) of
Subsection E of 19.8.20.2017 NMAC.
D. Coal processing waste banks. Coal
processing waste banks shall be designed to comply with the requirements of
19.8.20.2039 through 2042 NMAC.
E.
Coal processing waste dams and embankments. Coal processing waste dams and
embankments shall be designed to comply with the requirements of 19.8.20.2047
through 2049 NMAC. Each plan shall be submitted to the director as a part of
the permit application, and shall comply with the requirements of the mine
safety and health administration,
30
CFR 77.216-1 and
77.216-2
and the state engineer and shall contain the results of a geotechnical
investigation of the proposed dam or embankment foundation area, to determine
the structural competence of the foundation which will support the proposed dam
or embankment structure and the impounded material. The geotechnical
investigation shall be planned and supervised by an engineer or engineering
geologist, according to the following:
(1)
the number, location, and depth of borings and test pits shall be determined
using current prudent engineering practice for the size of the dam or
embankment, quantity of material to be impounded, and subsurface
conditions;
(2) the character of
the overburden and bedrock, the proposed abutment sites, and any adverse
geotechnical conditions which may affect the particular dam, embankment, or
reservoir site shall be considered;
(3) all springs, seepage, and ground water
flow observed or anticipated during wet periods in the area of the proposed dam
or embankment shall be identified on each plan;
(4) consideration shall be given to the
possibility of mudflows, rock debris falls, or other landslides into the dam,
embankment, or impounded material;
(5) if the structure meets the class B or C
criteria for dams in TR-60 or meets the size or other criteria of 30 CFR Sec.
77.216(a), each plan under Subsections B, C and E of 19.8.9.909 NMAC shall
include a stability analysis of the structure; the stability analysis shall be
performed by a registered professional engineer and shall include, but not be
limited to, strength parameters, pore pressures, and long-term seepage
conditions; the plan shall also contain a description of each engineering
design assumption and calculation with a discussion of each alternative
considered in selecting the specific design parameters and construction
methods.
