Current through Register Vol. 18, September 20, 2024
(1) The owner or
operator of a Class II landfill unit shall ensure that:
(a) the concentration of methane gas generated by
the facility does not exceed 25 percent of the lower explosive limit for methane in
facility structures, excluding gas control or recovery system components;
and
(b) the concentration of methane gas
does not exceed the lower explosive limit for methane at the facility property
boundary.
(2) The owner or
operator of a Class II landfill unit shall implement a routine methane monitoring
program to ensure that the standards of (1) are met.
(3) The minimum frequency of monitoring required
in (2) is quarterly, except as provided in (7). The type and frequency of monitoring
required in (2) must be determined based on the following factors:
(a) soil conditions;
(b) the hydrogeologic conditions surrounding the
facility;
(c) the hydraulic conditions
surrounding the facility;
(d) the
location of facility structures and property boundaries.
(4) If methane gas levels exceeding the limits
specified in (1) are detected, the owner or operator shall:
(a) immediately take all necessary steps to ensure
protection of human health and notify the department;
(b) within seven days after detection, place in
the operating record specification of the methane gas levels detected and a
description of the steps taken to protect human health; and
(c) within 60 days after detection, submit for
department approval, and implement, a remediation plan for controlling methane gas
releases, place a copy of the plan in the operating record, and notify the
department that the plan has been implemented.
(5) The remediation plan in (4)(c) must:
(a) describe the nature and extent of the problem
and the proposed remedy;
(b) provide
design plans for the proposed remedy; and
(c) for construction of all methane gas control
systems required in this rule, contain a submission for department approval that
includes plans, specifications, reports, and certifications to the same extent as
required in ARM
17.50.1205.
(6) The department may establish alternative
schedules for demonstrating compliance with (4)(b) and (c).
(7) The department may establish alternative
frequencies for the monitoring requirement of (3), after public review and comment,
for an owner or operator of a Class II landfill unit that disposes of 20 tons or
less of municipal solid waste per day, based on an annual average. Any alternative
monitoring frequencies established under this paragraph must:
(a) be based on the unique characteristics of
small communities;
(b) take into account
climatic and hydrogeologic conditions; and
(c) be protective of human health and the
environment.
75-10-204, MCA; IMP,
75-10-204,
MCA;
