Current through Register Vol. 48, No. 38, September 20, 2024
a)
Detection monitoring program:
Any use of the term "maximum allowable predicted
concentration" or "MAPC" in this Section is a reference to Section
817.414(c),
as defined in Section
811.102. The
operator shall implement a detection monitoring program in accordance with the
following requirements:
1) Monitoring
schedule and frequency:
A) The monitoring
period shall begin as soon as waste is placed into the unit of a new landfill
or within one year after August 1, 1994 for an existing landfill. Monitoring
shall continue for a minimum period of five years after closure or, in the case
of landfills, other than those used exclusively for disposing waste generated
at the site, a minimum of fifteen years after closure. The operator shall
sample all monitoring points for all potential sources of contamination on a
quarterly basis except as specified in subsection (a)(3) of this Section or may
institute more frequent sampling throughout the time the source constitutes a
threat to groundwater. For the purposes of this Section, the source shall be
considered a threat to groundwater if the results of the monitoring indicate
that the concentrations of any of the constituent monitored within the zone of
attenuation are above the MAPC for that constituent.
B) Beginning five years after closure of the
unit, or five years after all other potential sources of discharge no longer
constitute a threat to groundwater, as defined in subsection (a)(1)(A) of this
Section, the monitoring frequency may change on a well by well basis to an
annual schedule if either of the conditions listed in subsection (a)(1)(B)(i)
or (a)(1)(B)(ii) of this Section exist. However, monitoring shall return to a
quarterly schedule at any well where a statistically significant increase is
determined to have occurred in accordance with Section
817.416(e),
in the concentration of any constituent with respect to the previous sample.
i) All constituents monitored within the zone
of attenuation have returned to a concentration less than or equal to ten
percent of the MAPC; or
ii) All
constituents monitored within the zone of attenuation are less than or equal to
their MAPC for eight consecutive quarters.
C) Monitoring shall be continued for a
minimum period of five years after closure or, in the case of landfills, other
than those used exclusively for disposing waste generated at the site, a
minimum period of fifteen years after closure. Monitoring, beyond the minimum
period, may be discontinued under the following conditions:
i) No statistically significant increase is
detected in the concentration of any constituent above that measured and
recorded during the immediately preceding scheduled sampling for three
consecutive years, after changing to an annual monitoring frequency;
or
ii) Immediately after
contaminated leachate is no longer generated by the unit.
2) Criteria for choosing
constituents to be monitored:
A) The operator
shall monitor each well for constituents that will provide a means for
detecting groundwater contamination. Constituents shall be chosen for
monitoring if they meet the following requirements:
i) The constituent appears in, or is expected
to be in, the leachate; and
ii) The
Board has established a groundwater quality standard at 35 Ill. Adm. Code 620,
or the constituent may otherwise cause or contribute to groundwater
contamination.
B) One or
more indicator constituents, representative of the transport processes of
constituents in the leachate, may be chosen for monitoring in place of the
constituents it represents. The use of such indicator constituents must be
included in an Agency approved permit.
3) Organic chemicals monitoring:
A) The operator shall monitor each existing
well that is being used as part of the monitoring well network at the facility
within one year after August 1, 1994, and monitor each new well within three
months after its establishment. The monitoring required by this subsection
shall be for the organic chemicals listed in Section 817.Appendix A of this
Part. The analysis shall be at least as sensitive as the procedures provided at
40 CFR
141.40(1992), incorporated
by reference at 35 Ill. Adm. Code
810.104.
B) At least once every two years, the
operator shall monitor each well in accordance with subsection (a)(3)(A) of
this Section.
4)
Confirmation of monitored increase:
A) The
confirmation procedures of this Section shall be used only if the
concentrations of the constituents monitored can be measured at or above the
practical quantitation limit (PQL). The PQL is defined as the lowest
concentration that can be reliably measured within specified limits of
precision and accuracy under routine laboratory operating conditions. The
operator shall institute the confirmation procedures of subsection (a)(4)(B)
after notifying the Agency in writing, within 10 days, of the following
observed increases:
i) The concentration of
any constituent monitored in accordance with subsections (a)(1) and (a)(2) of
this Section shows a progressive increase over four consecutive
quarters;
ii) The concentration of
any constituent exceeds the MAPC at an established monitoring point within the
zone of attenuation;
iii) The
concentration of any constituent monitored in accordance with subsection (a)(3)
of this Section exceeds the preceding measured concentration at any established
monitoring point; and
iv) The
concentration of any constituent monitored at or beyond the zone of attenuation
exceeds the applicable groundwater quality standards of Section
817.416.
B) The
confirmation procedures shall include the following:
i) The operator shall verify any observed
increase by taking additional samples within 45 days after the initial
observation and ensure that the samples and sampling protocol used will detect
any statistically significant increase in the concentration of the suspect
constituent in accordance with 35 Ill. Adm. Code
811.320(e),
so as to confirm the observed increase. The operator shall notify the Agency of
any confirmed increase before the end of the next business day following the
confirmation. The verification procedure shall be completed within 90 days
after the initial sampling event.
ii) The operator shall determine the source
of any confirmed increase, which may include, but shall not be limited to,
natural phenomena, sampling or analysis errors, or an off-site
source.
iii) The operator shall
notify the Agency in writing of any confirmed increase and state the source of
the confirmed increase and provide the rationale used in such a determination
within ten days after the determination.
b) Assessment monitoring. The
operator shall begin an assessment monitoring program in order to confirm the
source of the contamination and to provide information needed to carry out a
groundwater impact assessment in accordance with subsection (c) of this
Section. The assessment monitoring program shall be conducted in accordance
with the following requirements:
1) The
assessment monitoring shall be conducted to collect information to assess the
nature and extent of groundwater contamination, which shall consist of, but not
be limited to, the following steps:
A) More
frequent sampling of the wells in which the observation occurred;
B) More frequent sampling of any surrounding
wells;
C) The placement of
additional monitoring wells to determine the source and extent of the
contamination;
D) Monitoring of
additional constituents to determine the source and extent of contamination;
and
E) Any other investigative
techniques that will assist in determining the nature and extent of the
contamination.
2) The
operator of the facility for which assessment monitoring is required shall file
the plans for an assessment monitoring program with the Agency. If the facility
is permitted by the Agency, then the plans shall be filed for review as a
significant permit modification pursuant to 35 Ill. Adm. Code 813.Subpart B.
The assessment monitoring program shall be implemented within 90 days after
confirmation of any monitored increase in accordance with subsection (a)(4) of
this Section or, in the case of permitted facilities, within 90 days after the
Agency approval. The assessment monitoring program shall be filed with the
Agency within 20 days after an observed increase, as defined in Section
817.415(a)(4)(B)(iii).
3) If the
analysis of the assessment monitoring data shows that the concentration of one
or more constituents, monitored at or beyond the zone of attenuation, is above
the applicable groundwater quality standards of Section
817.416
and is attributable to the solid waste disposal facility, the operator shall
determine the nature and extent of the groundwater contamination, including an
assessment of the continued impact on the groundwater should additional waste
continue to be accepted at the facility, and shall implement remedial action in
accordance with subsection (d) of this Section.
4) If the analysis of the assessment
monitoring data shows that the concentration of one or more constituents is
attributable to the solid waste disposal facility and exceeds the MAPC within
the zone of attenuation, then the operator shall conduct a groundwater impact
assessment in accordance with the requirements of subsection (c) of this
Section.
c) Assessment
of potential groundwater impact. An operator required to conduct a groundwater
impact assessment in accordance with subsection (b)(4) of this Section shall
assess the potential impacts outside the zone of attenuation that may result
from confirmed increases above the MAPC within the zone of attenuation,
attributable to the facility, in order to determine if there is need for
remedial action.
1) The operator shall
utilize any new information developed since the initial assessment and
information from the detection and assessment monitoring programs and such
information shall be used to develop a groundwater contaminant transport (GCT)
model in accordance with 35 Ill. Adm. Code
811.317(c);
and
2) The operator shall submit
the groundwater impact assessment, GCT modeling and results, and any proposed
remedial action plans determined necessary pursuant to subsection (d) to the
Agency within 180 days after the start of the assessment monitoring
program.
d) Remedial
action:
1) The operator shall submit plans
for the remedial action to the Agency. Such plans and all supporting
information including data collected during the assessment monitoring shall be
submitted within 90 days after determination after either of the following:
A) The groundwater impact assessment
performed in accordance with subsection (c) indicates that remedial action is
needed; or
B) Any confirmed
increase above the applicable groundwater quality standards of Section
817.416
is determined to be attributable to the solid waste disposal facility in
accordance with subsection (b).
2) If the facility has been issued a permit
by the Agency, then the operator shall submit this information as an
application for significant modification to the permit.
3) The operator shall implement the plan for
remedial action within 90 days after the following:
A) Completion of the groundwater impact
assessment under subsection (c) that requires remedial action;
B) Establishing that a violation of an
applicable groundwater quality standard of Section
817.416
is attributable to the solid waste disposal facility in accordance with
subsection (b)(3) above; or
C)
Agency approval of the remedial action plan, where the facility has been
permitted by the Agency.
4) The remedial action program shall consist
of one or a combination of the following solutions to meet the requirements of
subsection (d)(5) of this Section in a timely and appropriate manner:
A) Retrofit additional groundwater protective
measures within the unit;
B)
Construct an additional hydraulic barrier, such as a cutoff wall or slurry wall
system;
C) Pump and treat the
contaminated groundwater; or
D) Any
other Agency approved equivalent technique which will prevent further
contamination of groundwater.
5) Termination of the remedial action
program:
A) The remedial action program shall
continue in accordance with the plan until monitoring shows that the
concentrations of all monitored constituents are below the MAPC within the zone
of attenuation, and below the applicable groundwater quality standards of
Section
817.416
at or beyond the zone of attenuation, over a period of 4 consecutive
quarters.
B) The operator shall
submit to the Agency all information collected under subsection (d)(5)(A). If
the facility is permitted, the operator shall submit this information as an
application for significant modification of the permit.