Issue 3 - the Montana Secretary of State Website

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(2) Ground water monitoring requirements under ARM 17.50.1304 through
17.50.1307 for a Class II or Class IV landfill unit may be suspended by the
department if the owner or operator submits, and obtains department approval for, a
demonstration that there is no potential for migration of a constituent in Appendix I
or II to 40 CFR Part 258 (July 1, 2008) from that Class II or Class IV landfill unit to
the uppermost aquifer or underground drinking water source, as required in ARM
17.50.1204, during the active life of the unit and the post-closure care period. This
demonstration must be certified by a qualified ground water scientist, and must be
based upon:
(a) and (b) remain as proposed.
(3) The owner or operator of an existing Class II or Class IV landfill unit, or a
lateral expansion of that an existing Class II or Class IV landfill unit, except one
meeting the conditions of ARM 17.50.1203, shall comply with the ground water
monitoring requirements of ARM Title 17, chapter 50, subchapters 5 through 14.
(4) through (6) remain as proposed.
NEW RULE XXXVIII (17.50.1304) GROUND WATER MONITORING
SYSTEMS (1) An owner or operator required to monitor under this subchapter
shall install a ground water monitoring system that consists of a sufficient number of
wells, installed at appropriate locations and depths, to yield ground water samples
from the uppermost aquifer, or underground drinking water source, as required in
ARM 17.50.1204, that:
(a) through (a)(ii) remain as proposed.
(b) represent the quality of ground water passing the relevant point of
compliance specified by the department under ARM 17.50.1204(3). The
downgradient monitoring system must be installed at the relevant point of
compliance specified by the department under ARM 17.50.1204(3) that ensures
detection of ground water contamination in the uppermost aquifer, or underground
drinking water source, as required in ARM 17.50.1204. When physical obstacles
preclude installation of ground water monitoring wells at the relevant point of
compliance at existing disposal units, the downgradient monitoring system may be
installed at the closest practicable distance hydraulically downgradient from the
relevant point of compliance specified by the department under ARM 17.50.1204(3)
that ensures detection of ground water contamination in the uppermost aquifer, or
underground drinking water source, as required in ARM 17.50.1204.
(2) through (3) remain as proposed.
(4) The owner or operator of a Class II or Class IV landfill unit required to
monitor under this subchapter shall:
(a) submit a ground water monitoring plan to the department for approval
that includes:
(i) remain as proposed.
(ii) plans for the design, installation, development, and decommission of
piezometers or other measurement, sampling, and analytical devices; and
(iii) discussions of the anticipated ground water monitoring system and
schedule of sampling for closed portions of the facility, if applicable; and
(iv) any other information determined by the department to be necessary to
protect human health or the environment;
3-2/11/10 Montana Administrative Register