Current through Register Vol. 49, No. 13, September 23, 2024
Subpart 1.
Scope.
This part applies to owners and operators of facilities that
treat or store hazardous waste in piles, except as part
7045.0552 provides otherwise.
Alternatively, a pile of hazardous waste may be managed as a landfill under
part
7045.0638.
Subp. 2.
Protection from wind.
The owner or operator of a pile containing hazardous waste
which could be subject to dispersal by wind shall cover or otherwise manage the
pile so that wind dispersal is controlled.
Subp. 3.
Waste analysis.
In addition to the waste analyses required by part
7045.0564, the owner or operator
shall analyze a representative sample of waste from each incoming movement
before adding the waste to any existing pile, unless:
A. the only wastes the facility receives
which are amenable to piling are compatible with each other; or
B. the waste received is compatible with the
waste in the pile to which it is to be added.
The analyses conducted must be capable of differentiating
between the types of hazardous waste the owner or operator places in piles, so
that mixing of incompatible waste does not inadvertently occur. The analysis
must include a visual comparison of color and texture. As required by part
7045.0564, the waste analysis plan
must include analyses needed to comply with subparts
5 and
6. As required by part
7045.0584, the owner or operator
shall place the results of this analysis in the operating record of the
facility.
Subp.
4.
Containment.
If leachate or run-off from a pile is a hazardous waste, all
the requirements of item A or B must be met:
A. The pile must be placed on an impermeable
base that is compatible with the waste under the conditions of treatment or
storage.
The owner or operator shall design, construct, operate, and
maintain a run-on control system capable of preventing flow onto the active
portion of the pile during peak discharge from at least a 25-year storm.
The owner or operator shall design, construct, operate, and
maintain a run-off management system to collect and control at least the water
volume resulting from a 24-hour, 25-year storm.
Collection and holding facilities, such as tanks or basins,
associated with run-on and run-off control systems must be emptied or otherwise
managed expeditiously to maintain design capacity of the system.
B. The pile must be protected from
precipitation and run-on by some other means, and no liquids or wastes
containing free liquids may be placed in the pile. If collected leachate or
run-off is discharged through a point source to waters of the United States, it
is subject to the requirements of the Federal Water Pollution Control Act
Amendments of 1972, United States Code, title 33, section 1342, as
amended.
Subp. 4a.
Design and operating requirements.
The owner or operator of each new waste pile on which
construction commences after January 29, 1992, each lateral expansion of a
waste pile unit on which construction commences after July 29, 1992, and each
such replacement of an existing waste pile unit that is to commence reuse after
July 29, 1992, must install two or more liners and a leachate collection and
removal system above and between such liners, and operate the leachate
collection and removal systems, in accordance with part
7045.0534, subpart
3, item C, unless exempted
under part
7045.0534, subpart
3, item D or E; and must
comply with the procedures of part
7045.0630, subpart 1a, item B.
"Construction commences" and "existing facility" are defined in part
7045.0020.
Subp. 4b.
Action leakage rates.
A. The owner or operator of waste pile units
subject to subpart
4a must submit a proposed
action leakage rate to the commissioner when submitting the notice required
under subpart
4a. Within 60 days of
receipt of the notification, the commissioner will establish an action leakage
rate, either as proposed by the owner or operator or modified using the
criteria in this subpart, or extend the review period for up to 30 days. If no
action is taken by the commissioner before the original 60-day or extended
90-day review periods, the action leakage rate will be approved as proposed by
the owner or operator.
B. The
commissioner shall approve an action leakage rate for waste pile units subject
to subpart
4a. The action leakage rate
is the maximum design flow rate that the leak detection system can remove
without the fluid head on the bottom liner exceeding one foot. The action
leakage rate must include an adequate safety margin to allow for uncertainties
in the design (e.g., slope, hydraulic conductivity, thickness of drainage
material), construction, operation, and location of the leak detection system,
waste and leachate characteristics, likelihood and amounts of other sources of
liquids in the leak detection system, and proposed response actions (e.g., the
action leakage rate must consider decreases in the flow capacity of the system
over time resulting from siltation and clogging, rib layover and creep of
synthetic components of the system, overburden pressures, etc.).
C. To determine if the action leakage rate
has been exceeded, the owner or operator must convert the weekly flow rate from
the monitoring data obtained under subpart
9, to an average daily flow
rate (gallons per acre per day) for each sump. Unless the commissioner approves
a different calculation, the average daily flow rate for each sump must be
calculated weekly during the active life and closure period.
Subp. 5.
Special
requirements for ignitable or reactive waste.
Ignitable or reactive waste must not be placed in a pile
unless the waste and pile satisfy all applicable requirements of part
7045.1390:
A. addition of the waste to an existing pile
results in the waste or mixture no longer meeting the definition of ignitable
or reactive waste under part
7045.0131, subpart
2 or
5, and the addition complies
with part
7045.0562, subpart
2; and
B. the waste is managed in such a way that it
is protected from any material or conditions which may cause it to ignite or
react.
Subp. 6.
Special requirements for incompatible waste.
Incompatible wastes, or incompatible wastes and materials
must not be placed in the same pile, unless part
7045.0562, subpart
2 is followed.
A pile of hazardous waste that is incompatible with any waste
or other material located nearby must be adequately separated from the other
materials, or protected from them by means of a dike, berm, wall, or other
device. The purpose of this requirement is to prevent fires, explosions,
gaseous emissions, leaching, or other discharge of hazardous waste or hazardous
waste constituents which could result from the contact or mixing of
incompatible wastes or materials.
Hazardous wastes must not be piled on the same area where
incompatible wastes or materials were previously piled, unless that area has
been decontaminated sufficiently to ensure compliance with part
7045.0562, subpart
2.
Subp. 7.
Closure and postclosure
care.
At closure, the owner or operator shall:
A. remove or decontaminate all hazardous
waste, hazardous waste residues, contaminated containment system components,
such as liners, contaminated subsoils, and structures and equipment
contaminated with hazardous waste and leachate, and manage then as hazardous
waste, unless the owner or operator can demonstrate that the waste removed is
not a hazardous waste; or
B. close
the facility and perform postclosure care in accordance with the closure and
postclosure requirements for landfills under part
7045.0638, subpart
4, if, after removing or
decontaminating all residues and making all reasonable efforts to effect
removal or decontamination of contaminated components, subsoils, structures,
and equipment the owner or operator finds that not all contaminated subsoils
can be practicably removed or decontaminated.
Subp. 8.
Response actions.
A. The owner or operator of waste pile units
subject to subpart
4a must submit a response
action plan to the commissioner when submitting the proposed action leakage
rate under subpart
4b. The response action plan
must set forth the actions to be taken if the action leakage rate has been
exceeded. At a minimum, the response action plan must describe the actions
specified in item B.
B. If the flow
rate into the leak determination system exceeds the action leakage rate for any
sump, the owner or operator must:
(1) notify
the commissioner in writing of the exceedence within seven days of the
determination;
(2) submit a
preliminary written assessment to the commissioner within 14 days of the
determination, as to the amount of liquids, likely sources of liquids, possible
location, size, and cause of any leaks, and short-term actions taken and
planned;
(3) determine to the
extent practicable the location, size, and cause of any leak;
(4) determine whether waste receipts should
cease or be curtailed, whether any waste should be removed from the unit for
inspection, repairs, or controls, and whether or not the unit should be
closed;
(5) determine any other
short-term and longer-term actions to be taken to mitigate or stop any leaks;
and
(6) within 30 days after the
notification that the action leakage rate has been exceeded, submit to the
commissioner the results of the analyses specified in subitems (3) to (5), the
results of actions taken, and actions planned. Monthly thereafter, as long as
the flow rate in the leak detection system exceeds the action leakage rate, the
owner or operator must submit to the commissioner a report summarizing the
results of any remedial actions taken and actions planned.
C. To make the leak and/or remediation
determinations in item B, subitems (3) to (5), the owner or operator must:
(1) document the following assessments:
(a) assess the source of liquids and amounts
of liquids by source;
(b) conduct a
fingerprint, hazardous constituent, or other analyses of the liquids in the
leak detection system to identify the source of liquids and possible location
of any leaks, and the hazard and mobility of the liquid; and
(c) assess the seriousness of any leaks in
terms of potential for escaping into the environment; or
(2) document why such assessments are not
needed.
Subp.
9.
Monitoring and inspection.
An owner or operator required to have a leak detection system
under subpart
4a must record the amount of
liquids removed from each leak detection system sump at least once each week
during the active life and closure period.
Statutory Authority: MS s
116.07;
116.37
