Current through Register Vol. 24-06, March 15, 2024
(1)
Limited purpose landfills - Applicability.
(a) These standards apply to limited purpose
landfills . Landfills in this category include facilities which may encompass
considerable variations in waste types, site conditions, and operational
controls. The primary characteristic of a limited purpose landfill is that it
is not allowed to receive municipal solid waste.
(b) These standards do not apply to:
(i) Landfills regulated under chapter 173-351
WAC, Criteria for municipal solid waste landfills;
(ii) Landfills regulated under WAC
173-350-410
Inert waste landfills;
(iii)
Landfills regulated under chapter 173-306 WAC, Special incinerator ash
management standards;
(iv)
Landfills regulated under chapter 173-303 WAC, Dangerous waste regulations;
and
(v) Landfills regulated under
Title 40 C.F.R. Part 761, Polychlorinated Biphenyls (PCBs) Manufacturing,
Processing, Distribution in Commerce, and Use Prohibitions.
(2)
Limited
purpose landfills - Permit exemptions. There are no permit exemptions
for limited purpose landfills.
(3)
Limited purpose landfills - Permit requirements-Location. All
limited purpose landfills must be located to meet the following requirements:
(a) No landfill may be located over a
Holocene fault, in subsidence areas, or on or adjacent to an unstable slope or
other geologic features which could compromise the structural integrity of the
facility;
(b) No landfill's active
area may be located closer than one thousand feet to an existing water supply
well;
(c) No landfill's active area
may be located in a channel migration zone or within two hundred feet, measured
horizontally, of a stream, lake, pond, river, saltwater body, or in any wetland
. All facilities must conform to location restrictions established in local
shoreline management plans adopted pursuant to chapter 90.58 RCW, Shoreline
Management Act of 1971;
(d) No
landfill may be located within ten thousand feet of any airport runway
currently used by turbojet aircraft or five thousand feet of any airport runway
currently used by only piston-type aircraft unless the federal aviation
administration grants a waiver. This requirement is only applicable where a
landfill is used for disposing of wastes where a bird hazard to aircraft would
be created; and
(e) All landfills
must comply with the location standards specified in
RCW
70.95.060.
(4)
Limited purpose landfills - Permit
requirements - Design. All landfills must be designed and constructed to
meet the design standards of this subsection, the performance standards of WAC
173-350-040,
and must be appropriate for and compatible with the waste, the site, and the
operation.
(a) Landfill design must consider:
(i) Waste characterization;
(ii) Soil conditions;
(iii) Hydrogeologic conditions;
(iv) Hydraulic conditions;
(v) Contaminant fate and transport;
(vi) Topography;
(vii) Climate;
(viii) Seismic conditions;
(ix) The site capacity and each landfill
unit;
(x) Anticipated leachate
characteristics and quantity;
(xi)
Operational controls; and
(xii)
Environmental monitoring systems.
(b) Landfill gas control. Limited purpose
landfills must be designed to control methane and other explosive gases to
ensure they do not exceed:
(i) Twenty-five
percent of the lower explosive limit for the gases in facility structures
(excluding the gas control or recovery system components);
(ii) The l ower explosive limit for gases in
soil or i n ambient air at the property boundary or beyond; and
(iii) One hundred parts per million by volume
of hydrocarbons (expressed as methane) in off-site structures.
(c) Liner system design.
(i) Liner system performance standard.
Limited purpose landfills must be constructed in accordance with a design that:
(A) Will prevent the contamination of the
hydrostrati-graphic units identified in the hydrogeologic assessment of the
facility at the point of compliance as specified during the permitting process;
and
(B) Will meet the landfill gas
control requirements of (b) of this subsection.
(ii) Liner system design and construction.
The owner or operator of a limited purpose landfill must select one of the
three options for liner system design and construction described in (c)(ii)(A),
(B), and (C) of this subsection. The options described in (B) and (C) of this
subsection require that the owner or operator must demonstrate to the
satisfaction of the jurisdictional health department during the permitting
process that the proposed liner design will comply with the liner performance
standard of (c)(i) of this subsection and the specific requirements of this
item.
(A) Presumptive liner design. Limited
purpose landfills designed and constructed with the following composite liner
are presumed to meet the performance standard of (c)(i) of this subsection. The
presumptive liner design consists of the following two components:
(I) A lower component consisting of at least
a two-foot layer of compacted soil with a hydraulic conductivity of no more
than 1 × 10-7 cm/sec; and
(II) An upper component consisting of a
high-density polyethylene (HDPE) geomembrane with a minimum of 60- mil
thickness. The geomembrane must be installed in direct and uniform contact with
the lower component.
(B) Facility-specific liner design. Limited
purpose landfills may be designed and constructed with an engineered liner
system that the owner or operator demonstrates will meet the performance
standard of (c)(i) of this subsection. The final liner system must be
appropriate for and compatible with the characteristics of the site, the wastes
that are specified in a solid waste permit as allowed for disposal in the
landfill, and the operation of the facility.
(C) Operation without an engineered liner.
Limited purpose landfills may be designed and constructed without an engineered
liner system, if the owner or operator demonstrates to the satisfaction of the
jurisdictional health department during the permitting process that:
(I) The contaminant levels in the waste and
leachate are unlikely to pose an adverse impact to the environment;
and
(II) The ability of natural
soils to provide a barrier or reduce the concentration of contaminants provides
sufficient protection to meet the performance standards of WAC
173-350-040;
and
(III) The landfill will meet
the landfill gas control requirements of (b) of this subsection.
(iii) Liner separation
from groundwater. No landfill liner system may be constructed with the bottom
of the lowest component less than ten feet above the seasonal high level of
groundwater, unless a hydraulic gradient control system has been installed
which prevents groundwater from contacting the liner. For the purpose of this
section, groundwater includes any water-bearing unit which is horizontally and
vertically extensive, hydraulically recharged, and volumetrically significant
as to harm or endanger the integrity of the liner at any time.
(iv) Hydraulic gradient control system
performance standard. When incorporated into a landfill design, a demonstration
must be made during the permit process that the hydraulic gradient control
system can control ground-water fluctuations and maintain separation between
the controlled seasonal high level of groundwater and the bottom of the liner
system . The system must not negatively impact waters of the state or impede
the ability to collect representative samples of the groundwater at the point
of compliance. The demonstration must include:
(A) A discussion in the geologic and
hydrogeologic site characterization showing the effects from subsoil
settlement, changes in surrounding land uses, climatic trends or other impacts
affecting groundwater levels during the active life and post-closure period of
the landfill;
(B) A discussion of
the gradient control system's potential impacts on quality and quantity of
groundwater or surface water. This discussion must include potential impacts to
water users and instream flow and levels of surface waters in direct hydrologic
contact with the hydraulic gradient control system. Any available ground or
surface water quality data for hydrostrati-graphic units, springs, or surface
waters in direct hydrologic contact with the hydraulic gradient control system
must be included;
(C) A discussion
of how the hydraulic gradient control system will protect or impact the
structural integrity and performance of the liner system; and
(D) Design specifications for the proposed
ground and surface water monitoring systems.
(d) Leachate collection and control system
design. Except when a landfill is designed and constructed without an
engineered liner under (c)(ii)(C) of this subsection, limited purpose landfills
must be constructed in accordance with a design that:
(i) Provides for collection and removal of
leachate generated in the landfill;
(ii) Is capable of maintaining a leachate
head of less than one-foot over the liner system and less than two feet in
leachate sump areas;
(iii) Includes
a monitoring system capable of collecting representative samples of leachate
generated in the landfill; and
(iv)
Provides for leachate storage, treatment, or pretreat-ment to meet the
requirements of WAC
173-350-330
Surface impoundments and tanks, chapter 90.48 RCW, Water pollution control, and
the Federal Clean Water Act, as appropriate when leachate is to be discharged
from the facility.
(e)
Run-on/runoff control system design. Limited purpose landfills must be
constructed in accordance with a design that:
(i) Will prevent flow onto the active portion
of the landfill during the peak discharge from a twenty-five-year
storm;
(ii) Will prevent
unpermitted discharges from the active portion of the landfill resulting from a
twenty-five-year storm; and
(iii)
When located in a one hundred-year flood plain, the entrance and exit roads and
landfill practices do not restrict the flow of the base flood, reduce the
temporary water storage capacity of the flood plain, or result in washout of
solid waste.
(f) Final
closure system design.
(i) Final closure
performance standard. Limited purpose landfills must be closed in accordance
with a design that:
(A) Prevents exposure of
waste;
(B) Minimizes infiltration
(at a minimum, the design will prevent the generation of significant quantities
of leachate to eliminate the need for leachate removal by the end of the
post-closure period);
(C) Prevents
erosion from wind and water;
(D) Is
capable of sustaining native vegetation;
(E) Addresses anticipated settlement, with a
goal of achieving no less than two to five percent slope after
settlement;
(F) Provides sufficient
stability and mechanical strength and addresses potential freeze-thaw and
desiccation;
(G) Provides for the
management of run-on and runoff, preventing erosion or otherwise damaging the
closure cover;
(H) Minimizes the
need for post-closure maintenance;
(I) Provides for collection and removal of
methane and other gases generated in the landfill to meet the requirements of
(b) of this subsection. Landfill gas must be purified for sale, used for its
energy value, or flared when the quantity and quality of landfill gases will
support combustion. Landfill gases may be vented when they will not support
combustion. The collection and removal system must include a monitoring system
capable of collecting representative samples of gases generated in the
landfill; and
(J) Meets the
requirements of regulations, permits and policies administered by the
jurisdictional air pollution control authority or the department under chapter
70.94 RCW, Washington Clean Air Act and Section 110 of the Federal Clean Air
Act.
(ii) Final cover
design and construction. The owner or operator of a limited purpose landfill
must select one of the two options for final cover system design and
construction described in (e)(ii)(A) and (B) of this subsection. The option
described in (e)(ii)(B) of this subsection requires that the owner or operator
must demonstrate to the satisfaction of the jurisdictional health department
during the permitting process that the proposed final cover design will comply
with the final cover performance standards of (f)(i) of this subsection and the
specific requirements of this item.
(A)
Presumptive final closure cover design. Limited purpose landfills designed and
constructed with the following final closure cover are presumed to meet the
performance standards in (f)(i)(A) through (D) of this subsection. The
presumptive final closure cover consists of the following components:
(I) An antierosion layer consisting of a
minimum of two feet of earthen material of which at least twelve inches of the
uppermost layer is capable of sustaining native vegetation, seeded with grass
or other shallow rooted vegetation; and
(II) A geomembrane with a minimum of 30-mil
thickness, or a greater thickness that is commensurate with the ability to join
the geomembrane material and site characteristics such as slope, overlaying a
competent foundation.
(B) Facility-specific final cover. Limited
purpose landfills may be designed and constructed with an engineered final
cover system that the owner or operator demonstrates will meet the performance
standards of (f)(i) of this subsection. The final cover system must be
appropriate for and compatible with: The characteristics of the site, the
wastes that are specified in a solid waste permit as allowed for disposal in
the landfill, and the operation of the facility.
(g) Water balance and groundwater
contaminant fate and transport modeling. Any modeling performed for evaluating
a landfill design must meet the following performance standards:
(i) All water balance analysis must be
performed using:
(A) The Hydrologic
Evaluation of Landfill Performance (HELP) Model; or
(B) Alternate methods approved by the
jurisdictional health department. Alternate methods must have supporting
documentation establishing its ability to accurately represent the water
balance within the landfill unit.
(ii) Any groundwater and contaminant fate and
transport modeling must be conducted by a licensed professional in accordance
with the requirements of chapter 18.220 RCW, Geologists, and meet the following
performance standards:
(A) The model must have
supporting documentation that establishes the ability of those methods to
represent groundwater flow and contaminant transport under the conditions at
the site;
(B) The model must be
calibrated against site-specific field data;
(C) A sensitivity analysis must be conducted
to measure the model's response to changes in the values assigned to major
parameters, specific tolerances, and numerically assigned space and time
discretizations;
(D) The value of
the model's parameters requiring site-specific data must be based upon actual
field or laboratory measurements; and
(E) The values of the model's parameters that
do not require site-specific data must be supported by laboratory test results
or equivalent methods documenting the validity of the chosen parameter values.
(h) Seismic
impact zones. Limited purpose landfills located in seismic impact zones must be
designed and constructed so that all containment structures, including liners,
leachate collection systems, surface water control systems, gas management, and
closure cover systems are able to resist the maximum horizontal acceleration in
earth materials for the site.
(i)
The owner or operator of limited purpose landfills located in an unstable area
must demonstrate that engineering measures have been incorporated into the
landfill's design to ensure that the integrity of the structural components of
the landfill will not be disrupted. The owner or operator must place the
demonstration in the application for a permit. The owner or operator must
consider the following factors, at a minimum, when determining whether an area
is unstable:
(i) On-site or local soil
conditions that may result in significant differential settling, surface
rupture, or liquefaction;
(ii)
On-site or local geologic or geomorphologic features indicating differential
settling, surface rupture, or liquefaction; and
(iii) On-site or local human-made features or
events (both surface and subsurface) indicating differential settling, surface
rupture, or liquefaction.
(j) Setback requirements. Limited purpose
landfills must be designed to provide a setback of at least one hundred feet
between the active area and the property boundary. The setback must be
increased if necessary to:
(i) Control
nuisance odors, dust, and litter;
(ii) Provide a space for the placement of
monitoring wells, gas probes, run-on/runoff controls, and other design
elements; or
(iii) Provide
sufficient area to allow proper operation of the landfill and access to
environmental monitoring systems and facility structures.
(k) Access control and traffic requirements.
All limited purpose landfills must:
(i)
Provide controls to limit public access and prevent unauthorized vehicular
traffic, illegal dumping of wastes, and keep animals out, by use of artificial
barriers, natural barriers, or both, as appropriate to protect human health and
the environment. A lockable gate is required at each entry to the
landfill;
(ii) Provide approach and
exit roads of all-weather construction, with traffic separation and traffic
control on-site, and at the site entrance; and
(iii) Provide a sign at the entrance that
identifies the facility and provides emergency contact information.
(5)
Limited
purpose landfills - Permit requirements -Documentation.
(a) The owner or operator must submit
construction documents for, at a minimum, any proposed addition or modification
of elements of the landfill described in subsection (4) of this section to the
jurisdictional health department for review and approval. The construction
documents for proposed construction of engineered features must be prepared by
a professional engineer registered in the state of Washington, and must
include:
(i) An engineering report that
presents the design basis and calculations for the engineered features of the
facility including, but not limited to: Liners, final closure covers,
impoundments, stormwater management features, leachate management features, and
aeration and emission control features as required by the permitting air
authority where applicable. The engineering report must demonstrate that the
proposed design will meet the performance standards of this chapter;
(ii) Scale drawings of the facility including
the location and size of waste storage and disposal areas, fixed equipment,
buildings, stormwater management features where applicable, access roads,
traffic patterns, and other constructed areas and buildings integral to
facility operation;
(iii) Design
specifications for the engineered features of the facility including, but not
limited to, liners, final closure covers, stormwater management features,
leachate management features, and aeration and emission management features as
required by a permitting air authority where applicable; and
(iv) A construction quality assurance plan
that describes monitoring, testing, and documentation procedures that will be
performed during construction of the facility to ensure the facility is
constructed in accordance with the approved design.
(b) The owner or operator of a limited
purpose landfill must provide copies of the construction record drawings for
engineered features at the facility and a report documenting facility
construction, including the results of observations and testing carried out as
part of the construction quality assurance plan, to the jurisdictional health
department and the department. The owner or operator must not commence
operation in a newly constructed portion of the facility until the
jurisdictional health department has determined that the construction was
completed in accordance with the approved engineering report/plans and
specifications and has approved the construction documentation in
writing.
(6)
Limited purpose landfills - Permit requirements -Operating . The
owner or operator of a limited purpose landfill must:
(a) Operate the facility in compliance with
the performance standards of WAC
173-350-040
and this subsection. In addition, the owner or operator must develop, keep, and
follow a plan of operation approved as part of the permitting process. The plan
must describe the facility's operation and convey to site operating personnel
the concept of operation intended by the designer. The plan of operation must
be available for inspection at the request of the jurisdictional health
department. If necessary, the plan may be modified with the approval, or at the
direction, of the jurisdictional health department. Each plan of operation must
include the following:
(i) A description of
the types of solid waste to be handled at the facility;
(ii) A description of the criteria and
procedures used to ensure that dangerous waste and other unacceptable waste,
including liquid waste, are not accepted at the facility;
(iii) A description of how solid wastes are
to be handled on-site, including identification of unloading and staging area,
transportation practices, and housekeeping activities;
(iv) A description of how the owner or
operator will ensure the facility is operated to:
(A) Protect containment and monitoring
structures such as liners, leachate collection systems, surface water control
systems, gas management, cover systems, and monitoring wells;
(B) Control litter, dust, and nuisance
odors;
(C) Control rodents,
insects, and other vectors;
(D)
Provide attendant(s) on-site during hours of operation; and
(E) Prevent scavenging.
(v) If the landfill's capacity is greater
than fifty thousand cubic yards per year, acknowledgment that at least two
landfill personnel will be on-site with one person at the active face when the
site is open to the public;
(vi) A
description of how waste will be landfilled, including:
(A) How solid waste will be compacted before
succeeding layers are added, except that the first lift over a liner may be
left uncompacted to act as a cushion for subsequent lifts;
(B) How cover of disposed waste will be
managed. Putrescible waste must be covered at the end of each operating day, or
at more frequent intervals if necessary. The jurisdictional health department
may grant a temporary waiver, not to exceed three months, from this cover
requirement if the owner or operator demonstrates that there are extreme
seasonal climatic conditions that make meeting these requirements impractical.
Materials used for cover must be:
(I) At
least six inches of earthen material, such as soils; or
(II) Alternative materials or an alternative
thickness other than at least six inches of earthen material as approved by the
jurisdictional health department when the owner or operator demonstrates that
the alternative material or thickness will control vectors, fires, nuisance
odors, blowing litter, scavenging, provide adequate access for heavy vehicles,
and will not adversely affect gas or leachate composition and
controls.
(vii) A description of how any explosive
gases generated at the facility will be monitored and controlled, and how the
owner or operator will respond to the detection of explosive gases in a manner
that ensures protections of human health. This element of the plan must
include, at a minimum:
(A) Controls to ensure
that explosive gases generated by the facility do not exceed the criteria of
subsection (4)(b) of this section;
(B) A routine explosive gas-monitoring
program to ensure that all standards are met. The minimum frequency for
monitoring is quarterly. The type and frequency of monitoring must be
determined based on the following factors:
(I) Soil conditions;
(II) The hydrogeologic conditions surrounding
the facility;
(III) The hydraulic
conditions surrounding the facility; and
(IV) The location of facility structures and
property boundaries;
(C)
If explosive gas levels exceed the limits identified in subsection (4)(b) of
this section, take all necessary steps to ensure protection of human health
including:
(I) Notifying the jurisdictional
health department;
(II) Notifying
the local fire authority;
(III)
Monitoring off-site structures;
(IV) Monitoring explosive gas levels daily,
unless otherwise authorized by the jurisdictional health department;
(V) Evacuating buildings affected by landfill
gas until determined to be safe for occupancy;
(VI) Within seven calendar days of the
explosive gas levels detection, placing in the operating record the explosive
gas levels detected and a description of the steps taken to protect human
health and providing written notification to the jurisdictional health
department;
(VII) Within sixty
days of the explosive gas levels detection, implementing a remediation plan for
the explosive gas releases, describing the nature and extent of the problem and
the remedy. This plan must be sent to the jurisdictional health department for
approval as an amendment to the plan of operation. A copy of the remediation
plan shall be placed in the operating record; and
(VIII) When constructing and decommissioning
gas monitoring and extraction wells, do so in a manner that protects
groundwater and meets the requirements of chapter 173-160 WAC, Minimum
standards for construction and maintenance of wells.
(viii) A description of how
equipment, structures and other systems, including leachate collection, gas
collection, run-on/runoff controls, and hydraulic gradient control systems, are
to be inspected and maintained, including the frequency of inspection and
inspection logs. The inspections must be at least weekly, unless an alternate
schedule is approved by the jurisdictional health department as part of the
permitting pro-cess;
(ix) A
description of how operators will maintain operating records on the amounts
(weight or volume) and types of waste received and removed from the facility,
and the number of vehicles delivering waste to the facility, including the form
or computer printout used to record this information. Facility annual reports
must be maintained in the operating record. Facility inspection reports must be
maintained in the operating record, including at least the date of inspection,
the name and signature of the inspector, a notation of observations made, and
the date and nature of any needed repairs or remedial action. Significant
deviations from the plan of operation must be noted in the operating record.
Records must be kept for a minimum of five years and must be available upon
request by the jurisdictional health department;
(x) A description of safety planning and
emergency activities, including:
(A) On-site
fire protection, as determined by the local and state fire control
jurisdiction. Landfills disposing of wastes that can support combustion must
have a method to control subsurface fires;
(B) Communications sufficient to handle
emergencies will be provided between employees working at the landfill and
management offices, on-site and off-site;
(C) Response procedures in the event of fire
(including subsurface fires), a description of fire protection equipment
available on-site and actions to take if there is a fire or explosion;
and
(D) Response procedures in the
event leachate or gas leaks are detected, or other releases occur.
(xi) Other details to demonstrate
that the landfill will be operated in accordance with this subsection and as
required by the jurisdictional health department.
(b) Prepare and submit a monitoring plan to
the jurisdictional health department describing all gas, leachate, surface
water, and groundwater monitoring to be conducted in order to meet the
requirements of subsections (4) and (5) of this section, as well as WAC
173-350-500
for groundwater. This plan must be approved by the jurisdictional health
department before being implemented. The jurisdictional health department may
specify a periodic review schedule for the plan. This monitoring plan must:
(i) Provide appropriate, consistent sampling
and analysis procedures designed to produce representative results. As
appropriate, the plan must include procedures for:
(A) Sample collection and handling;
(B) Sample preservation and
shipment;
(C) Analytical
procedures;
(D) Chain-of-custody
control;
(E) Quality assurance and
quality control; and
(F)
Decontamination of equipment.
(ii) The sampling and analytical methods must
provide sufficient sensitivity, precision, selectivity and limited bias so that
changes in conditions can be detected and quantified. All laboratory analyzed
samples must be sent to an accredited laboratory for analyses according to
chapter 173-50 WAC, Accreditation of environmental laboratories.
(c) Prepare and submit a landfill
annual status report and an annual monitoring report to the jurisdictional
health department and the department by April 1st of each year on forms
provided by the department. These annual reports must cover landfill activities
during the previous calendar year and must include the following information:
(i) Name and address of the
facility;
(ii) Calendar year
covered by the report;
(iii) Annual
quantities and types of waste accepted in tons or cubic yards with an estimate
of density in pounds per cubic yard;
(iv) Applicable financial assurance reviews
and audit findings in accordance with WAC
173-350-600;
and
(v) Any additional information
required by the jurisdictional health department as a condition of the
per-mit.
(7)
Limited purpose landfills - Permit requirements - Groundwater
monitoring. Limited purpose landfills are subject to the groundwater
monitoring requirements of WAC
173-350-500.
(8)
Limited purpose landfills - Permit
requirements - Closure. The following requirements apply to facilities
with limited purpose landfills:
(a) The owner
or operator must develop, keep, and follow a closure plan approved by the
jurisdictional health department as part of the permitting process. At a
minimum, the closure plan must include the following information:
(i) A description of the final closure cover,
designed in accordance with subsection (4)(e) of this section, the methods and
procedures to be used to install the closure cover, sources of borrow materials
for the closure cover, and a schedule or description of the time required for
completing closure activities;
(ii)
Projected time intervals at which sequential partial closure and final closure
are to be implemented;
(iii) A
description of the activities and procedures that will be used to ensure
compliance with (b) through (f) of this subsection; and
(iv) Identify closure cost estimated and
projected fund withdrawal intervals for the associated closure costs, from the
approved financial assurance instrument.
(b) When the facility is ending active
disposal operations the owner or operator must notify the jurisdictional health
department, and where applicable, the financial assurance instrument provider,
one hundred eighty days in advance of closure of the facility, or any portion
thereof. The facility, or any portion thereof, must close in a manner that:
(i) Minimizes the need for further
maintenance;
(ii) Controls,
minimizes, or eliminates threats to human health and the environment from
post-closure escape of solid waste constituents, leachate, landfill gases,
contaminated runoff, or waste decomposition products to the ground,
groundwater, surface water, and the atmosphere; and
(iii) Prepares the facility, or any portion
thereof, for the post-closure period.
(c) The owner or operator must commence
implementation of the closure plan in part or whole within thirty days after
receipt of the final volume of waste and/or attaining the final landfill
elevation at part of or at the entire landfill as identified in the approved
facility closure plan unless otherwise specified in the closure plan;
(d) When landfill closure is completed in
part or whole, the owner or operator must submit to the jurisdictional health
department a certification by a professional engineer registered in the state
of Washington, that the landfill, or a portion thereof, has been closed in
accordance with the approved closure plan;
(e) Environmental covenant. Following closure
of a limited purpose landfill, the owner operator must file an environmental
covenant conforming to the procedures and requirements of chapter 64.70 RCW,
Uniform Environmental Covenants Act. Unless waived in writing by the
department, the environmental covenant must be in a form approved by the
department and include at a minimum the following provisions:
(i) State that the document is an
environmental covenant executed pursuant to chapter 64.70 RCW, Uniform
Environmental Covenants Act;
(ii)
Contain a legally sufficient description of the real property subject to the
covenant;
(iii) Designate the
department, or other person approved by the department, as the holder of the
covenant;
(iv) Be signed by the
department, every holder, and, unless waived by the department, every owner of
a fee simple interest in the real property subject to the covenant;
(v) Identify the name and location of the
administrative record for the property subject to the environmental
covenant;
(vi) Describe with
specificity the activity or use limitations on the real property subject to the
covenant. At a minimum, this must prohibit uses and activities that:
(A) Threaten the integrity of any cover,
waste containment, stormwater control, gas leachate, public access control, or
environmental monitoring systems;
(B) May interfere with the operation and
maintenance, monitoring, or other measures necessary to assure the integrity of
the landfill and continued protection of human health and the environment;
and
(C) May result in the release
of solid waste constituents or otherwise exacerbate exposures.
(vii) Grant the department and the
jurisdictional health department the right to enter the property at reasonable
times for the purpose of evaluating compliance with the environmental covenant,
including the right to take samples.
(f) The jurisdictional health department will
notify the owner or operator, the department, and the financial assurance
instrument provider, of the date when the jurisdictional health department has
verified that the facility, or a portion thereof, has been closed in accordance
with the specifications of the approved closure plan and the closure
requirements of this section, at which time the post-closure period
commences.
(9)
Limited purpose landfills - Permit requirements - Financial
assurance.
(a) Financial assurance is
required for all limited purpose landfills.
(b) Each owner or operator must establish a
financial assurance mechanism in accordance with WAC
173-350-600
that will accumulate funds equal to the closure and post-closure cost estimates
over the life of the landfill, or over the life of each landfill unit if closed
discretely.
(c) No owner or
operator may commence or continue disposal operations in any part of a facility
subject to this section until a financial assurance instrument has been
provided for closure and post-closure activities in accordance with WAC
173-350-600.
(10)
Limited purpose
landfills - Permit application contents. The owner or operator must
obtain a solid waste permit from the jurisdictional health department. All
applications for permits must be in accordance with the procedures established
in WAC
173-350-710.
In addition to the requirements of WAC
173-350-710
and
173-350-715,
each application for a permit must contain:
(a) Demonstrations that the facility meets
the location standards of subsection (3) of this section;
(b) Documentation that all owners of property
located within one thousand feet of the boundary of the landfill as it is
proposed to be located in the solid waste permit application have been notified
that the proposed facility may impact their ability to construct water supply
wells, in accordance with chapter 173-160 WAC, Minimum standards for
construction and maintenance of wells;
(c) Engineering reports, plans, and
specifications that address the standards of subsections (4) and (5) of this
section;
(d) A construction quality
assurance plan that addresses the requirements of subsection (5) of this
section;
(e) A plan of operation
meeting the requirements of subsection (6) of this section;
(f) Hydrogeologic reports and plans that
address the requirements of subsection (7) of this section;
(g) A closure plan meeting the requirements
of subsection (8) of this section;
(h) A post-closure plan meeting the
requirements of subsection (11) of this section; and
(i) Documentation as needed to meet the
financial assurance requirements of subsection (9) of this section.
(11)
Limited purpose
landfills - Post-closure care requirements.
(a) The owner or operator must conduct
post-closure care for as long as necessary for the landfill to become
functionally stable. A landfill is functionally stable when it does not present
a threat to human health or the environment at the point of exposure for humans
or environmental receptors. The point of exposure is identified as the closest
location at which a receptor could be exposed to contaminants and receive a
dose by a credible pathway from the landfill. Potential threats to human health
or the environment are assessed by considering leachate quality and quantity,
landfill gas production rate and composition, cover system integrity, and
groundwater quality. The post-closure care period may be adjusted under (b) of
this subsection. Post-closure care must consist of at least the following:
(i) Maintaining the integrity and
effectiveness of any final cover, including making repairs to the cover as
necessary to correct the effects of settlement, subsidence, erosion,
maintaining the vegetative cover (including cutting of vegetation when needed)
or other events, and preventing run-on and runoff from eroding or otherwise
damaging the final cover;
(ii)
Monitoring the groundwater, surface water, leachate, landfill gas, and landfill
settlement according to the monitoring plan described in subsection (6)(b) of
this section, including any monitoring of remedial measures if applicable, and
maintaining all monitoring systems;
(iii) Maintaining and operating the leachate
collection system under subsection (4)(d) of this section, if applicable. The
jurisdictional health department may recommend to the department, and the
department may, under its authority in chapter 90.48 RCW, Water pollution
control, allow the owner or operator to stop managing leachate if the owner or
operator demonstrates that leachate no longer poses a threat to human health
and the environment;
(iv)
Maintaining and operating the landfill gas collection and control system under
subsections (4)(f)(i)(I) and (6)(a)(vii) of this section; and
(v) Maintaining, operating and monitoring
hydraulic gradient control systems if applicable;
(vi) Maintaining the facility and facility
structures for their intended uses; and
(vii) Performing any other activities deemed
appropriate by the jurisdictional health department.
(b) The jurisdictional health department and
owner or operator will consider at least the following factors when determining
when a landfill unit is functionally stable or whether to decrease or increase
the post-closure care period:
(i) Leachate.
The landfill's production and quality of leachate must have attained a state
where maintenance and operation of the leachate collection system can be
discontinued without posing a threat to human health or the
environment;
(ii) Landfill gas. The
landfill's production and composition of gas must have attained a state where
maintenance and operation of the gas collection system can be discontinued
while meeting the criteria in subsection (4)(b) of this section and not pose a
threat to human health or the environment from methane or nonmethane compounds;
(iii) Settlement and cover
integrity. The cover system must attain geotechnical stability for slope and
settlement. Vegetation and other erosion controls must prevent exposing waste
or otherwise threaten integrity of the cover system. The cover system must have
attained a state where no additional care is required to ensure its integrity
from settlement or erosion; and
(iv) Groundwater quality. Groundwater quality
must remain in compliance with the performance standards of WAC
173-350-040
at the point of compliance.
(c) The owner or operator must commence
post-closure activities for the facility, or portion thereof, after completion
of closure procedures and activities outlined in subsection (8) of this
section;
(d) The owner or operator
must develop, keep, and follow a post-closure plan approved by the
jurisdictional health department as a part of the permitting process. The
post-closure plan must:
(i) Address facility
maintenance and monitoring activities for the duration of the post-closure care
period; and
(ii) Project time
intervals at which post-closure activities are to be implemented, and identify
post-closure cost estimates and projected fund withdrawal intervals from the
selected financial assurance instrument, where applicable, for the associated
post-closure costs.
(e)
The owner or operator must complete post-closure activities for the facility,
or portion thereof, in accordance with the approved post-closure plan and
schedule, or the plan must be so amended with the approval of the
jurisdictional health department;
(f) When post-closure activities are
complete, the owner or operator must submit a certification to the
jurisdictional health department, signed by the owner or operator, and a
professional engineer registered in the state of Washington stating why
post-closure activities are no longer necessary;
(g) If the jurisdictional health department
finds that post-closure monitoring has established that the landfill is
functionally stable, the health department may authorize the owner or operator
to discontinue post-closure maintenance and monitoring activities;
and
(h) The jurisdictional health
department must notify the owner or operator, the department, and the financial
assurance instrument provider, of the date when the jurisdictional health
department has verified that the facility has completed post-closure activities
in accordance with the specifications of the approved post-closure
plan.
Statutory Authority:
Chapter
70.95 RCW. 03-03-043
(Order 99-24), § 173-350-400, filed 1/10/03, effective
2/10/03.