Current through August 26, 2024
(1) Drip pads shall
comply with all of the following:
(a) Be
constructed of non-earthen materials, excluding wood and non-structurally
supported asphalt.
(b) Be sloped to
free-drain treated wood drippage, rain and other waters, or solutions of
drippage and water or other wastes to the associated collection
system.
(c) Have a curb or berm
around the perimeter.
(d)
1. Have a hydraulic conductivity of less than
or equal to 1X10 -7 centimeters per second, e.g., existing concrete drip pads
shall be sealed, coated or covered with a surface material with a hydraulic
conductivity of less than or equal to 1X10 -7 centimeters per second such that
the entire surface where drippage occurs or may run across is capable of
containing the drippage and mixtures of drippage and precipitation, materials
or other wastes while being routed to an associated collection system. This
surface material shall be maintained free of cracks and gaps that could
adversely affect its hydraulic conductivity, and the material shall be
chemically compatible with the preservatives that contact the drip pad. The
requirements of this provision apply only to existing drip pads and those drip
pads for which the owner or operator elects to comply with s.
NR 664.0572(2) instead of s.
NR 664.0572(1).
2. The owner or operator shall obtain and
keep on file at the facility a written assessment of the drip pad, reviewed and
certified by a qualified professional engineer that attests to the results of
the evaluation. The assessment shall be reviewed, updated and recertified
annually. The evaluation shall document the extent to which the drip pad meets
the design and operating standards of this section, except for sub.
(2).
(e) Be of
sufficient structural strength and thickness to prevent failure due to physical
contact, climatic conditions and the stress of daily operations, including
variable and moving loads such as vehicle traffic or movement of wood.
Note: The department will generally consider
applicable standards established by professional organizations generally
recognized by the industry such as the American Concrete Institute (ACI) or the
American Society of Testing and Materials (ASTM) in judging the structural
integrity requirement of par. (e).
(2) If an owner or operator elects to comply
with s.
NR 664.0572(1) instead of s.
NR 664.0572(2), the drip pad shall have
all of the following:
(a) A synthetic liner
installed below the drip pad that is designed, constructed and installed to
prevent leakage from the drip pad into the adjacent subsurface soil or
groundwater or surface water at any time during the active life (including the
closure period) of the drip pad. The liner shall be constructed of materials
that will prevent waste from being absorbed into the liner and to prevent
releases into the adjacent subsurface soil or groundwater or surface water
during the active life of the facility. The liner shall comply with all of the
following:
1. Be constructed of materials
that have appropriate chemical properties and sufficient strength and thickness
to prevent failure due to pressure gradients (including static head and
external hydrogeologic forces), physical contact with the waste or drip pad
leakage to which they are exposed, climatic conditions, the stress of
installation and the stress of daily operation (including stresses from
vehicular traffic on the drip pad).
2. Be placed upon a foundation or base
capable of providing support to the liner and resistance to pressure gradients
above and below the liner to prevent failure of the liner due to settlement,
compression or uplift.
3. Be
installed to cover all surrounding earth that could come in contact with the
waste or leakage.
(b) A
leakage detection system immediately above the liner that is designed,
constructed, maintained and operated to detect leakage from the drip pad. The
leakage detection system shall comply with all of the following:
1. Be constructed of materials that are all
of the following:
a. Chemically resistant to
the waste managed in the drip pad and the leakage that might be
generated.
b. Of sufficient
strength and thickness to prevent collapse under the pressures exerted by
overlaying materials and by any equipment used at the drip pad.
2. Be designed and operated to
function without clogging through the scheduled closure of the drip
pad.
3. Be designed so that it will
detect the failure of the drip pad or the presence of a release of hazardous
waste or accumulated liquid at the earliest practicable time.
(c) A leakage collection system
immediately above the liner that is designed, constructed, maintained and
operated to collect leakage from the drip pad such that it can be removed from
below the drip pad. The date, time and quantity of any leakage collected in
this system and removed shall be documented in the operating log.
(3) Drip pads shall be maintained
such that they remain free of cracks, gaps, corrosion or other deterioration
that could cause hazardous waste to be released from the drip pad.
Note: See sub. (13) for remedial action
required if deterioration or leakage is detected.
(4) The drip pad and associated collection
system shall be designed and operated to convey, drain and collect liquid
resulting from drippage or precipitation in order to prevent run-off.
(5) Unless protected by a structure, as
described in s.
NR 664.0570(2), the owner or operator
shall design, construct, operate and maintain a run-on control system capable
of preventing flow onto the drip pad during peak discharge from at least a
24-hour, 25-year storm, unless the system has sufficient excess capacity to
contain any run-off that might enter the system.
(6) Unless protected by a structure or cover
as described in s.
NR 664.0570(2), 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.
(7) The drip pad shall be
evaluated to determine that it meets the requirements of subs. (1) to (6), and
the owner or operator shall obtain a statement from a qualified professional
engineer certifying that the drip pad design meets the requirements of this
section.
(8) Drippage and
accumulated precipitation shall be removed from the associated collection
system as necessary to prevent overflow onto the drip pad.
(9) The drip pad surface shall be cleaned
thoroughly in a manner and frequency such that accumulated residues of
hazardous waste or other materials are removed, with residues being properly
managed as hazardous waste, so as to allow weekly inspections of the entire
drip pad surface without interference or hindrance from accumulated residues of
hazardous waste or other materials on the drip pad. The owner or operator shall
document the date and time of each cleaning and the cleaning procedure used in
the facility's operating log. The owner or operator shall determine if the
residues are hazardous per s.
NR 662.011 and, if so, shall manage them under chs. NR
661 to 668, 670 and s.
291.05(1),
Stats.
(10) Drip pads shall be
operated and maintained in a manner to minimize tracking of hazardous waste or
hazardous waste constituents off the drip pad as a result of activities by
personnel or equipment.
(11) After
being removed from the treatment vessel, treated wood from pressure and
non-pressure processes shall be held on the drip pad until drippage has ceased.
The owner or operator shall maintain records sufficient to document that all
treated wood is held on the pad following treatment in accordance with this
requirement.
(12) Collection and
holding units associated with run-on and run-off control systems shall be
emptied or otherwise managed as soon as possible after storms to maintain
design capacity of the system.
(13)
Throughout the active life of the drip pad and as specified in the license, if
the owner or operator detects a condition that may have caused or has caused a
release of hazardous waste, the condition shall be repaired within a reasonably
prompt period of time following discovery, in accordance with all of the
following procedures:
(a) Upon detection of a
condition that may have caused or has caused a release of hazardous waste
(e.g., upon detection of leakage in the leak detection system), the owner or
operator shall do all of the following:
1.
Enter a record of the discovery in the facility operating log.
2. Immediately remove the portion of the drip
pad affected by the condition from service.
3. Determine what steps must be taken to
repair the drip pad and clean up any leakage from below the drip pad, and
establish a schedule for accomplishing the repairs.
4. Immediately after discovery of the
condition, notify the department of the condition and, within 10 working days,
provide written notice to the department with a description of the steps that
will be taken to repair the drip pad and clean up any leakage, and the schedule
for accomplishing this work.
(b) The department will review the
information submitted, make a determination regarding whether the pad must be
removed from service completely or partially until repairs and clean up are
complete and notify the owner or operator of the determination and the
underlying rationale in writing.
(c) Upon completing all repairs and clean up,
the owner or operator shall notify the department in writing and provide a
certification signed by an independent, qualified registered professional
engineer, that the repairs and clean up have been completed according to the
written plan submitted in accordance with par. (a) 4.
(14) Should a license be necessary, the
department will specify in the license all design and operating practices that
are necessary to ensure that the requirements of this section are
satisfied.
(15) The owner or
operator shall maintain, as part of the facility operating log, documentation
of past operating and waste handling practices. This shall include
identification of preservative formulations used in the past, a description of
drippage management practices and a description of treated wood storage and
handling practices.
