Current through Register Vol. 6, March 22, 2024
(1) Each
application must contain, where applicable, a narrative explaining the
construction, modification, use, maintenance, removal, and reclamation of coal
processing waste removal, handling, storage, transportation and disposal sites
and structures in the permit area in accordance with ARM
17.24.932, including appropriate
maps that meet the requirements of ARM
17.24.305 and describing the
location of each source of waste, waste storage area, and waste disposal
structure.
(2) Each application
must contain a general plan and detailed design plan for each coal processing
waste disposal area and structure proposed within the permit area.
(a) Each general plan must:
(i) be prepared by, or under the direction of
and certified by a qualified licensed professional engineer experienced in the
construction of earth and rock fill embankments;
(ii) contain a description, a map prepared
according to ARM 17.24.305, and appropriate cross-sections of the structure and
its location;
(iii) contain
hydrologic and geologic information required to assess the hydrologic impact of
the structure;
(iv) contain a
survey describing the potential effect on the structure from subsidence of the
subsurface strata resulting from past or future underground mining activities;
and
(v) contain a certification
statement that includes a schedule setting forth the dates that any detailed
design plan for structures that are not submitted with the general plan will be
submitted to the department. The department must have approved, in writing, the
detailed design plan for a structure before construction of the structure
begins.
(b) Each detailed
design plan for a structure must:
(i) be
prepared by, or under the direction of, and certified by a qualified registered
professional engineer experienced in the construction of earth and rock
embankments with assistance from experts in related fields such as geology,
land surveying, and landscape architecture;
(ii) describe the operation and maintenance
requirements for each structure;
(iii) describe the timetable and plans to
remove each structure, if appropriate; and
(iv) include geotechnical investigations and
design and construction specifications for the structure.
(3) If the application includes a
proposal to impound coal processing waste, the following is required:
(a) design information and impoundment
operation that meets the requirements of ARM
17.24.505(5);
(b) demonstration of compliance with the
requirements of 30 CFR
77.216-1 and
77.216-2;
(c) the results of a geotechnical
investigation of the proposed dam or embankment and impoundment foundation
areas to determine the structural competence of the geological materials there
to support the dam or embankment and impounded wastes. The geotechnical
investigation must be planned and supervised by an engineer or engineering
geologist in accordance with the following criteria:
(i) the number, location, and depth of
borings and test pits must be determined using current prudent engineering
practice for the size of the dam or embankment, quantity of wastes to be
impounded, and subsurface conditions;
(ii) the character of the overburden and
bedrock, the proposed abutment sites, and any adverse geotechnical conditions
which may affect the particular dam, embankment, or impoundment site must be
considered;
(iii) all springs,
seepage, and ground water flow observed or anticipated during wet periods in
the area of the proposed dam or embankment must be identified;
(iv) consideration must be given to the
possibility of mudflows, rock-debris falls, or other landslides into the dam,
embankment, or impounded wastes; and
(d) if the dam or embankment is at least 20
feet high or the impoundment has a proposed capacity of more than 20 acre-feet:
(i) a stability analysis, which must include,
but not be limited to, strength parameters, pore pressures, and long-term
seepage conditions; and
(ii) a
description of each engineering design assumption and calculation with a
discussion of each option considered in selecting the specific design
parameters and construction methods.