Current through Register Vol. 49, No. 13, September 23, 2024
Subpart 1.
General requirements.
The owner or operator of a surface impoundment, landfill, or
land treatment facility which is used to manage hazardous waste shall implement
a ground water monitoring program capable of determining the facility's impact
on the quality of ground water in the uppermost aquifer underlying the
facility, except as subparts
2 and
3 and part
7045.0552 provide
otherwise.
Except as subparts
2,
3, and
5 provide otherwise, the
owner or operator shall install, operate, and maintain a ground water
monitoring system which meets the requirements of subparts
4 and
5, and must comply with
subparts
6,
7, and
8 and part
7045.0592. This ground water
monitoring program must be carried out during the active life of the facility,
and for disposal facilities, during the postclosure care period as well.
Subp. 2.
Neutralization
surface impoundments.
The ground water monitoring requirements of this part and
part
7045.0592, may be waived by the
commissioner with respect to any surface impoundment that:
A. Is used to neutralize wastes which are
hazardous only because they exhibit the corrosivity characteristic under part
7045.0131, subpart
4, or are listed as hazardous
wastes in part
7045.0135 only for
corrosivity.
B. Contains no other
hazardous wastes, if the owner or operator can demonstrate that there is no
potential for migration of hazardous wastes from the impoundment. The
demonstration must establish, based upon consideration of the characteristics
of the wastes and the impoundment, that the corrosive wastes will be
neutralized to the extent that they no longer meet the corrosivity
characteristic before they can migrate out of the impoundment. This
demonstration must be in writing and must be certified by a qualified
professional, and submitted to the commissioner for review.
Subp. 3.
Waiving of ground
water monitoring requirements.
All or part of the ground water monitoring requirements of
this part and part
7045.0592 may be waived if the
owner or operator can demonstrate that there is a low potential for migration
of hazardous waste or hazardous waste constituents from the facility via the
uppermost aquifer to water supply wells including domestic, industrial, or
agricultural or to surface water. This demonstration must be in writing, and
must be kept at the facility. This demonstration must be certified by a
qualified geologist or geotechnical engineer and must establish the
following:
A. the potential for
migration of hazardous waste or hazardous waste constituents from the facility
to the uppermost aquifer, by an evaluation of:
(1) a water balance of precipitation,
evapotranspiration, run-off, and infiltration; and
(2) unsaturated zone characteristics
including geologic materials, physical properties, and depth to ground water;
and
B. the potential for
hazardous waste or hazardous waste constituents which enter the uppermost
aquifer to migrate to a water supply well or surface water, by an evaluation
of:
(1) saturated zone characteristics
including geologic materials, physical properties, and rate of ground water
flow; and
(2) the proximity of the
facility to water supply wells or surface water.
Subp. 4.
Ground water
monitoring system.
Requirements of ground water monitoring systems are as
follows:
A. A ground water monitoring
system must be capable of yielding ground water samples for analysis and must
consist of:
(1) At least one monitoring well
installed hydraulically upgradient from the limit of the waste management area.
Their number, construction, location, and depth must be sufficient to yield
ground water samples that are representative of background ground water quality
in the uppermost aquifer near the facility, and not affected by the facility;
and
(2) At least three monitoring
wells installed hydraulically downgradient at the limits of the waste
management area. Their number, locations, and depths must ensure that they
immediately detect any statistically significant amounts of hazardous waste or
hazardous waste constituents that migrate from the waste management area to the
uppermost aquifer.
B.
Separate monitoring systems for each waste management component of a facility
are not required provided that provisions for sampling upgradient and
downgradient water quality will detect any discharge from the waste management
area.
In the case of a facility consisting of only one surface
impoundment, landfill, or land treatment area, the waste management area is
described by the waste boundary.
In the case of a facility consisting of more than one surface
impoundment, landfill, or land treatment area, the waste management area is
described by an imaginary boundary line which circumscribes the several waste
management components.
C.
All monitoring wells must be cased in a manner that maintains the integrity of
the monitoring well bore hole. The hole must be screened and packed with gravel
or sand where necessary, to enable sample collection at depths where
appropriate aquifer flows exist. Where necessary, wells must be properly
developed to enable collection of representative ground water samples. The
annular space, meaning the space between the bore hole and the well casing,
above the sampling depth must be sealed with a suitable material, such as
cement grout or bentonite slurry, to prevent contamination of samples and the
ground water. All monitoring wells must be constructed in accordance with the
Minnesota Water Well Construction Code in chapter 4725.
Subp. 5.
Alternate ground water
monitoring systems.
If an owner or operator assumes or knows that ground water
monitoring of indicator parameters in accordance with subparts
4, items A and B, and 6 would
show statistically significant increases, or decreases in the case of pH, when
evaluated under item A, he or she may install, operate, and maintain an
alternate ground water monitoring system other than the one described in
subparts
4 and
6. If the owner or operator
decides to use an alternate ground water monitoring system, he or she
shall:
A. within one year after July
16, 1984, submit to the commissioner a specific plan, certified by a qualified
geologist or geotechnical engineer, which satisfies the requirements of part
7045.0592, subpart
4, item C, for an alternate
ground water monitoring system;
B.
not later than one year after July 16, 1984, initiate the determinations
specified in part
7045.0592, subpart
4, item D;
C. prepare and submit a written report in
accordance with part
7045.0592, subpart
4, item E;
D. continue to make the determination
specified in part
7045.0592, subpart
4, item D on a quarterly
basis until final closure of the facility; and
E. comply with the record keeping and
reporting requirements in subpart
7.
Subp. 6.
Sampling and analysis.
The sampling and analysis process is as follows:
A. The owner or operator shall obtain and
analyze samples from the installed ground water monitoring system. The owner or
operator shall develop and follow a ground water sampling and analysis plan. He
or she shall keep this plan at the facility. The plan shall include procedures
and techniques for: sample collection, sample preservation and shipment,
analytical procedures, and chain of custody control.
B. The owner or operator shall determine the
concentration or value of the following parameters in ground water samples in
accordance with items C and D:
(1) Parameters
characterizing the suitability of the ground water as a drinking water supply,
as specified in Code of Federal Regulations, title 40, part 265, appendix III,
as amended.
(2) Parameters
establishing ground water quality include chloride, iron, manganese, phenols,
sodium, and sulfate. These parameters are to be used as a basis for comparison
in the event a ground water quality assessment is required under part
7045.0592.
(3) Parameters used as indicators of ground
water contamination are pH, specific conductance, total organic carbon, and
total organic halogen.
(4)
Waste-specific parameters where not covered in item A and subitems (1) to (3)
determined by the commissioner as appropriate to the waste managed at the
facility.
C. For all
monitoring wells, the owner or operator shall establish initial background
concentrations or values of all parameters specified in item B quarterly for
one year.
For each of the indicator parameters specified in item B,
subitem (3), and determined pursuant to item B, subitem (4), at least four
replicate measurements must be obtained for each sample and the initial
background arithmetic mean and variance must be determined by pooling the
replicate measurements for the respective parameter concentrations or values in
samples obtained from upgradient wells during the first year.
D. After the first year, all monitoring wells
must be sampled and the samples analyzed with the following frequencies:
(1) samples collected to establish ground
water quality must be obtained and analyzed for the parameters specified in
item B, subitem (2), at least annually; and
(2) samples collected to indicate ground
water contamination must be obtained and analyzed for the parameters specified
in item B, subitem (3), and determined pursuant to item B, subitem (4), at
least quarterly.
E.
Elevation of the ground water surface at each monitoring well must be
determined each time a sample is obtained.
Subp. 7.
Record keeping.
Unless the ground water is monitored to satisfy the
requirements of part
7045.0592, subpart
4, item D, the owner or
operator shall keep records of the analyses required in subpart
6, items C and D, the
associated ground water surface elevations required in subpart
6, item E, and the
evaluations required in part
7045.0592, subpart
2, throughout the active life
of the facility, and, for disposal facilities, throughout the postclosure care
period as well.
If the ground water is monitored to satisfy the requirements
of part
7045.0592, subpart
4, item D, the owner or
operator shall keep records of the analyses and evaluations specified in the
plan, which satisfies the requirements of part
7045.0592, subpart
4, item C, throughout the
active life of the facility, and for disposal facilities, throughout the
postclosure care period as well.
Subp.
8.
Reporting.
Reporting requirements are as follows:
A. Unless the ground water is monitored to
satisfy the requirements of part
7045.0592, subpart
4, item D, the owner or
operator shall report the following ground water monitoring information to the
commissioner:
(1) During the first year when
initial background concentrations are being established for the facility, the
owner or operator shall report concentrations or values of the parameters
listed in subpart
6, item B, subitem (1), for
each ground water monitoring well within 15 days after completing each
quarterly analysis. The owner or operator shall separately identify for each
monitoring well any parameters whose concentration or value has been found to
exceed the maximum contaminant levels listed in Code of Federal Regulations,
title 40, part 265, appendix III, as amended.
(2) The owner or operator shall annually
report concentrations or values of the parameters listed in subpart
6, item B, subitem (3) or
(4), for each ground water monitoring well, along with the required evaluations
for these parameters under part
7045.0592, subpart
2. The owner or operator
shall separately identify any significant differences from initial background
found in the upgradient wells, in accordance with part
7045.0592, subpart
3. During the active life of
the facility this information must be submitted as part of the annual report
required under part
7045.0588, subpart
2.
(3) As a part of the annual report required
under part
7045.0588, subpart
2, the owner or operator
shall report results of the evaluation of ground water surface elevations under
part
7045.0592, subpart
6, and a description of the
response to that evaluation, where applicable.
B. If the ground water is monitored to
satisfy the requirements of part
7045.0592, subpart
4, item D, the owner or
operator shall annually, until final closure of the facility, submit to the
commissioner a report containing the results of his or her ground water quality
assessment program which includes, but is not limited to, the calculated or
measured rate of migration of hazardous waste or hazardous waste constituents
in the ground water during the reporting period. This report must be submitted
as part of the annual report required under part
7045.0588, subpart
2.
Statutory Authority: MS s
116.07
