WAC 173-350-100
Definitions. When used in this chapter,
the following terms have the meanings given below.
"Active area" means that portion of a facility where
solid waste recycling, reuse, treatment, storage, or disposal
operations are being, are proposed to be, or have been
conducted. Setbacks shall not be considered part of the
active area of a facility.
"Agricultural composting" means composting of
agricultural waste as an integral component of a system
designed to improve soil health and recycle agricultural
wastes. Agricultural composting is conducted on lands used
for farming.
"Agricultural wastes" means wastes on farms resulting
from the raising or growing of plants and animals including,
but not limited to, crop residue, manure and animal bedding,
and carcasses of dead animals weighing each or collectively in
excess of fifteen pounds.
"Agronomic rates" means the application rate (dry weight
basis) that will provide the amount of nitrogen or other
critical nutrient required for optimum growth of vegetation,
and that will not result in the violation of applicable
standards or requirements for the protection of ground or
surface water as established under chapter 90.48 RCW, Water
pollution control and related rules including chapter 173-200
WAC, Water quality standards for groundwaters of the state of
Washington, and chapter 173-201A WAC, Water quality standards
for surface waters of the state of Washington.
"Air quality standard" means a standard set for maximum
allowable contamination in ambient air as set forth in chapter 173-400 WAC, General regulations for air pollution sources.
"Below ground tank" means a device meeting the definition
of "tank" in this chapter where a portion of the tank wall is
situated to any degree within the ground, thereby preventing
visual inspection of that external surface of the tank that is
in the ground.
"Beneficial use" means the use of solid waste as an
ingredient in a manufacturing process, or as an effective
substitute for natural or commercial products, in a manner
that does not pose a threat to human health or the
environment. Avoidance of processing or disposal cost alone
does not constitute beneficial use.
"Biosolids" means municipal sewage sludge that is a
primarily organic, semisolid product resulting from the
wastewater treatment process, that can be beneficially
recycled and meets all applicable requirements under chapter 173-308 WAC, Biosolids management. Biosolids includes a
material derived from biosolids and septic tank sludge, also
known as septage, that can be beneficially recycled and meets
all applicable requirements under chapter 173-308 WAC,
Biosolids management.
"Buffer" means a permanently vegetated strip adjacent to
an application area, the purpose of which is to filter runoff
or overspray from the application area and protect an adjacent
area.
"Cab cards" means a license carried in a vehicle that
authorizes that vehicle to legally pick up waste tires and
haul to a permitted, licensed facility or an exempt facility
for deposit.
"Captive insurance companies" means companies that are
wholly owned subsidiaries controlled by the parent company and
established to insure the parent company or its other
subsidiaries.
"Channel migration zone" means the lateral extent of
likely movement of a stream or river channel along a stream
reach.
"Clean soils and clean dredged material" means soils and
dredged material which are not dangerous wastes, contaminated
soils, or contaminated dredged material as defined in this
section.
"Closure" means those actions taken by the owner or
operator of a solid waste handling facility to cease disposal
operations or other solid waste handling activities, to ensure
that all such facilities are closed in conformance with
applicable regulations at the time of such closures and to
prepare the site for the post-closure period.
"Closure plan" means a written plan developed by an owner
or operator of a facility detailing how a facility is to close
at the end of its active life.
"Composted material" means organic solid waste that has
undergone biological degradation and transformation under
controlled conditions designed to promote aerobic
decomposition at a solid waste facility in compliance with the
requirements of this chapter. Natural decay of organic solid
waste under uncontrolled conditions does not result in
composted material.
"Composting" means the biological degradation and
transformation of organic solid waste under controlled
conditions designed to promote aerobic decomposition. Natural
decay of organic solid waste under uncontrolled conditions is
not composting.
"Conditionally exempt small quantity generator (CESQG)"
means a dangerous waste generator whose dangerous wastes are
not subject to regulation under chapter 70.105 RCW, Hazardous
waste management, solely because the waste is generated or
accumulated in quantities below the threshold for regulation
and meets the conditions prescribed in WAC 173-303-070 (8)(b).
"Conditionally exempt small quantity generator (CESQG)
waste" means dangerous waste generated by a conditionally
exempt small quantity generator.
"Container" means a portable device used for the
collection, storage, and/or transportation of solid waste
including, but not limited to, reusable containers, disposable
containers, and detachable containers.
"Contaminant" means any chemical, physical, biological,
or radiological substance that does not occur naturally in the
environment or that occurs at concentrations greater than
natural background levels.
"Contaminate" means the release of solid waste, leachate,
or gases emitted by solid waste, such that contaminants enter
the environment at concentrations that pose a threat to human
health or the environment, or cause a violation of any
applicable environmental regulation.
"Contaminated dredged material" means dredged material
resulting from the dredging of surface waters of the state
where contaminants are present in the dredged material at
concentrations not suitable for open water disposal and the
dredged material is not dangerous waste and is not regulated
by section 404 of the Federal Clean Water Act (P.L. 95-217).
"Contaminated soils" means soils removed during the
cleanup of a hazardous waste site, or a dangerous waste
facility closure, corrective actions or other clean-up
activities and which contain harmful substances but are not
designated dangerous wastes.
"Corrosion expert" means a person certified by the
National Association of Corrosion Engineers (NACE) or a
registered professional engineer who has certification or
licensing that includes education and experience in corrosion
control.
"Crop residues" means vegetative material leftover from
the harvesting of crops, including leftover pieces or whole
fruits or vegetables, crop leaves and stems. Crop residue
does not include food processing waste.
"Dangerous wastes" means any solid waste designated as
dangerous waste by the department under chapter 173-303 WAC,
Dangerous waste regulations.
"Department" means the Washington state department of
ecology.
"Detachable containers" means reusable containers that
are mechanically loaded or handled, such as a dumpster or drop
box.
"Disposable containers" means containers that are used
once to handle solid waste, such as plastic bags, cardboard
boxes and paper bags.
"Disposal" or "deposition" means the discharge, deposit,
injection, dumping, leaking, or placing of any solid waste
into or on any land or water.
"Domestic septage" means Class I, II or III domestic
septage as defined in chapter 173-308 WAC, Biosolids
management.
"Domestic wastewater facility" means all structures,
equipment, or processes required to collect, carry away,
treat, reclaim, or dispose of domestic wastewater together
with such industrial waste as may be present.
"Drop box facility" means a facility used for the
placement of a detachable container including the area
adjacent for necessary entrance and exit roads, unloading and
turn-around areas. Drop box facilities normally serve the
general public with loose loads and receive waste from
offsite.
"Energy recovery" means the recovery of energy in a
useable form from mass burning or refuse-derived fuel
incineration, pyrolysis or any other means of using the heat
of combustion of solid waste that involves high temperature
(above twelve hundred degrees Fahrenheit) processing.
"Existing facility" means a facility which is owned or
leased, and in operation, or for which facility construction
has begun, on or before the effective date of this chapter and
the owner or operator has obtained permits or approvals
necessary under federal, state and local statutes, regulations
and ordinances.
"Facility" means all contiguous land (including buffers
and setbacks) and structures, other appurtenances, and
improvements on the land used for solid waste handling.
"Facility construction" means the continuous on-site
physical act of constructing solid waste handling unit(s) or
when the owner or operator of a facility has entered into
contractual obligations for physical construction of the
facility that cannot be canceled or modified without
substantial financial loss.
"Facility structures" means constructed infrastructure
such as buildings, sheds, utility lines, and piping on the
facility.
"Garbage" means animal and vegetable waste resulting from
the handling, storage, sale, preparation, cooking, and serving
of foods.
"Groundwater" means that part of the subsurface water
that is in the zone of saturation.
"Holocene fault" means a plane along which earthen
material on one side has been displaced with respect to that
on the other side and has occurred in the most recent epoch of
the Quaternary period extending from the end of the
Pleistocene to the present.
"Home composting" means composting of on-site generated
wastes, and incidental materials beneficial to the composting
process, by the owner or person in control of a single-family
residence, or for a dwelling that houses two to five families,
such as a duplex or clustered dwellings.
"Household hazardous wastes" means any waste which
exhibits any of the properties of dangerous wastes that is
exempt from regulation under chapter 70.105 RCW, Hazardous
waste management, solely because the waste is generated by
households. Household hazardous waste can also include other
solid waste identified in the local hazardous waste management
plan prepared pursuant to chapter 70.105 RCW, Hazardous waste
management.
"Hydrostratigraphic unit" means any water-bearing
geologic unit or units hydraulically connected or grouped
together on the basis of similar hydraulic conductivity which
can be reasonably monitored; several geologic formations or
part of a geologic formation may be grouped into a single
hydrostratigraphic unit; perched sand lenses may be considered
a hydrostratigraphic unit or part of a hydrostratigraphic
unit, for example.
"Incineration" means reducing the volume of solid wastes
by use of an enclosed device using controlled flame
combustion.
"Incompatible waste" means a waste that is unsuitable for
mixing with another waste or material because the mixture
might produce excessive heat or pressure, fire or explosion,
violent reaction, toxic dust, fumes, mists, or gases, or
flammable fumes or gases.
"Industrial solid wastes" means solid waste generated
from manufacturing operations, food processing, or other
industrial processes.
"Industrial wastewater facility" means all structures,
equipment, or processes required to collect, carry away,
treat, reclaim, or dispose of industrial wastewater.
"Inert waste" means solid wastes that meet the criteria
for inert waste in WAC 173-350-990.
"Inert waste landfill" means a landfill that receives
only inert wastes.
"Intermediate solid waste handling facility" means any
intermediate use or processing site engaged in solid waste
handling which is not the final site of disposal. This
includes material recovery facilities, transfer stations, drop
boxes, baling and compaction sites.
"Intermodal facility" means any facility operated for the
purpose of transporting closed containers of waste and the
containers are not opened for further treatment, processing or
consolidation of the waste.
"Jurisdictional health department" means city, county,
city-county or district public health department.
"Land application site" means a contiguous area of land
under the same ownership or operational control on which solid
wastes are beneficially utilized for their agronomic or
soil-amending capability.
"Land reclamation" means using solid waste to restore
drastically disturbed lands including, but not limited to,
construction sites and surface mines. Using solid waste as a
component of fill is not land reclamation.
"Landfill" means a disposal facility or part of a
facility at which solid waste is permanently placed in or on
land including facilities that use solid waste as a component
of fill.
"Leachate" means water or other liquid within a solid
waste handling unit that has been contaminated by dissolved or
suspended materials due to contact with solid waste or gases.
"Limited moderate risk waste" means waste batteries,
waste oil, and waste antifreeze generated from households.
"Limited moderate risk waste facility" means a facility
that collects, stores, and consolidates only limited moderate
risk waste.
"Limited purpose landfill" means a landfill which is not
regulated or permitted by other state or federal environmental
regulations that receives solid wastes limited by type or
source. Limited purpose landfills include, but are not
limited to, landfills that receive segregated industrial solid
waste, construction, demolition and landclearing debris, wood
waste, ash (other than special incinerator ash), and dredged
material. Limited purpose landfills do not include inert
waste landfills, municipal solid waste landfills regulated
under chapter 173-351 WAC, Criteria for municipal solid waste
landfills, landfills disposing of special incinerator ash
regulated under chapter 173-306 WAC, Special incinerator ash
management standards, landfills regulated under chapter 173-303 WAC, Dangerous waste regulations, or chemical waste
landfills used for the disposal of polychlorinated biphenyls
(PCBs) regulated under Title 40 CFR Part 761, Polychlorinated
Biphenyls (PCBs) Manufacturing, Processing, Distribution in
Commerce, and Use Prohibitions.
"Liquid" means a substance that flows readily and assumes
the form of its container but retains its independent volume.
"Liquid waste" means any solid waste which is deemed to
contain free liquids as determined by the Paint Filter Liquids
Test, Method 9095, in "Test Methods for Evaluating Solid
Waste, Physical/Chemical Methods," EPA Publication SW-846.
"Lithified earth material" means all rock, including all
naturally occurring and naturally formed aggregates or masses
of minerals or small particles of older rock that formed by
crystallization of magma or by induration of loose sediments.
This term does not include man-made materials, such as fill,
concrete or asphalt, or unconsolidated earth materials, soil
or regolith lying at or near the earth's surface.
"Local fire control agency" means a public or private
agency or corporation providing fire protection such as a
local fire department, the department of natural resources or
the United States Forest Service.
"Lower explosive limits" means the lowest percentage by
volume of a mixture of explosive gases that will propagate a
flame in air at twenty-five degrees centigrade and atmospheric
pressure.
"Material recovery facility" means any facility that
collects, compacts, repackages, sorts, or processes for
transport source separated solid waste for the purpose of
recycling.
"Mobile systems and collection events" means activities
conducted at a temporary location to collect moderate risk
waste.
"Moderate risk waste (MRW)" means solid waste that is
limited to conditionally exempt small quantity generator
(CESQG) waste and household hazardous waste (HHW) as defined
in this chapter.
"MRW facility" means a solid waste handling unit that is
used to collect, treat, recycle, exchange, store, consolidate,
and/or transfer moderate risk waste. This does not include
mobile systems and collection events or limited MRW facilities
that meet the applicable terms and conditions of WAC 173-350-360 (2) or (3).
"Municipal solid waste (MSW)" means a subset of solid
waste which includes unsegregated garbage, refuse and similar
solid waste material discarded from residential, commercial,
institutional and industrial sources and community activities,
including residue after recyclables have been separated.
Solid waste that has been segregated by source and
characteristic may qualify for management as a non-MSW solid
waste, at a facility designed and operated to address the
waste's characteristics and potential environmental impacts.
The term MSW does not include:
▪ Dangerous wastes other than wastes excluded from the
requirements of chapter 173-303 WAC, Dangerous waste
regulations, in WAC 173-303-071 such as household hazardous
wastes;
▪ Any solid waste, including contaminated soil and
debris, resulting from response action taken under section 104
or 106 of the Comprehensive Environmental Response,
Compensation and Liability Act of 1980 (42 U.S.C. 9601),
chapter 70.105D RCW, Hazardous waste cleanup -- Model Toxics
Control Act, chapter 173-340 WAC, the Model Toxics Control Act
cleanup regulation or a remedial action taken under those
rules; nor
▪ Mixed or segregated recyclable material that has been
source-separated from garbage, refuse and similar solid waste.
The residual from source separated recyclables is MSW.
"Natural background" means the concentration of chemical,
physical, biological, or radiological substances consistently
present in the environment that has not been influenced by
regional or localized human activities. Metals at
concentrations naturally occurring in bedrock, sediments and
soils due solely to the geologic processes that formed the
materials are natural background. In addition, low
concentrations of other persistent substances due solely to
the global use or formation of these substances are natural
background.
"New solid waste handling unit" means a solid waste
handling unit that begins operation or facility construction,
and significant modifications to existing solid waste handling
units, after the effective date of this chapter.
"Nuisance odor" means any odor which is found offensive
or may unreasonably interfere with any person's health,
comfort, or enjoyment beyond the property boundary of a
facility.
"One hundred-year flood plain" means any land area that
is subject to one percent or greater chance of flooding in any
given year from any source.
"Open burning" means the burning of solid waste materials
in an open fire or an outdoor container without providing for
the control of combustion or the control of emissions from the
combustion.
"Overburden" means the earth, rock, soil, and topsoil
that lie above mineral deposits.
"Permeability" means the ease with which a porous
material allows liquid or gaseous fluids to flow through it.
For water, this is usually expressed in units of centimeters
per second and termed hydraulic conductivity.
"Permit" means an authorization issued by the
jurisdictional health department which allows a person to
perform solid waste activities at a specific location and
which includes specific conditions for such facility
operations.
"Person" means an individual, firm, association,
copartnership, political subdivision, government agency,
municipality, industry, public or private corporation, or any
other entity whatever.
"Pile" means any noncontainerized accumulation of solid
waste that is used for treatment or storage.
"Plan of operation" means the written plan developed by
an owner or operator of a facility detailing how a facility is
to be operated during its active life.
"Point of compliance" means a point established in the
groundwater by the jurisdictional health department as near a
possible source of release as technically, hydrogeologically
and geographically feasible.
"Post-closure" means the requirements placed upon
disposal facilities after closure to ensure their
environmental safety for at least a twenty-year period or
until the site becomes stabilized (i.e., little or no
settlement, gas production, or leachate generation).
"Post-closure plan" means a written plan developed by an
owner or operator of a facility detailing how a facility is to
meet the post-closure requirements for the facility.
"Premises" means a tract or parcel of land with or
without habitable buildings.
"Private facility" means a privately owned facility
maintained on private property solely for the purpose of
managing waste generated by the entity owning the site.
"Processing" means an operation to convert a material
into a useful product or to prepare it for reuse, recycling,
or disposal.
"Product take-back center" means a retail outlet or
distributor that accepts household hazardous waste of
comparable types as the products offered for sale or
distributed at that outlet.
"Public facility" means a publicly or privately owned
facility that accepts solid waste generated by other persons;
"Putrescible waste" means solid waste which contains
material capable of being readily decomposed by microorganisms
and which is likely to produce offensive odors.
"Pyrolysis" means the process in which solid wastes are
heated in an enclosed device in the absence of oxygen to
vaporization, producing a hydrocarbon-rich gas capable of
being burned for recovery of energy.
"Recyclable materials" means those solid wastes that are
separated for recycling or reuse, including, but not limited
to, papers, metals, and glass, that are identified as
recyclable material pursuant to a local comprehensive solid
waste plan.
"Recycling" means transforming or remanufacturing waste
materials into usable or marketable materials for use other
than landfill disposal or incineration. Recycling does not
include collection, compacting, repackaging, and sorting for
the purpose of transport.
"Representative sample" means a sample that can be
expected to exhibit the average properties of the sample
source.
"Reserved" means a section having no requirements and
which is set aside for future possible rule making as a note
to the regulated community.
"Reusable containers" means containers that are used more
than once to handle solid waste, such as garbage cans.
"Runoff" means any rainwater, leachate or other liquid
that drains over land from any part of the facility.
"Run-on" means any rainwater or other liquid that drains
over land onto any part of a facility.
"Scavenging" means the removal of materials at a disposal
facility, or intermediate solid waste-handling facility,
without the approval of the owner or operator and the
jurisdictional health department.
"Seismic impact zone" means an area with a ten percent or
greater probability that the maximum horizontal acceleration
in lithified earth material, expressed as a percentage of the
earth's gravitational pull, will exceed 0.10g in two hundred
fifty years.
"Setback" means that part of a facility that lies between
the active area and the property boundary.
"Sewage sludge" means solid, semisolid, or liquid residue
generated during the treatment of domestic sewage in a
treatment works. Sewage sludge includes, but is not limited
to, domestic septage; scum or solids removed in primary,
secondary, or advanced wastewater treatment processes; and a
material derived from sewage sludge. Sewage sludge does not
include ash generated during the firing of sewage sludge in a
sewage sludge incinerator or grit and screenings generated.
"Soil amendment" means any substance that is intended to
improve the physical characteristics of soil, except composted
material, commercial fertilizers, agricultural liming agents,
unmanipulated animal manures, unmanipulated vegetable manures,
food wastes, food processing wastes, and materials exempted by
rule of the department, such as biosolids as defined in
chapter 70.95J RCW, Municipal sewage sludge -- Biosolids and
wastewater, as regulated in chapter 90.48 RCW, Water pollution
control.
"Solid waste" or "wastes" means all putrescible and
nonputrescible solid and semisolid wastes including, but not
limited to, garbage, rubbish, ashes, industrial wastes, swill,
sewage sludge, demolition and construction wastes, abandoned
vehicles or parts thereof, contaminated soils and contaminated
dredged material, and recyclable materials.
"Solid waste handling" means the management, storage,
collection, transportation, treatment, use, processing or
final disposal of solid wastes, including the recovery and
recycling of materials from solid wastes, the recovery of
energy resources from such wastes or the conversion of the
energy in such wastes to more useful forms or combinations
thereof.
"Solid waste handling unit" means discrete areas of land,
sealed surfaces, liner systems, excavations, facility
structures, or other appurtenances within a facility used for
solid waste handling.
"Source separation" means the separation of different
kinds of solid waste at the place where the waste originates.
"Storage" means the holding of solid waste materials for
a temporary period.
"Surface impoundment" means a facility or part of a
facility which is a natural topographic depression, man-made
excavation, or diked area formed primarily of earthen
materials (although it may be lined with man-made materials),
and which is designed to hold an accumulation of liquids or
sludges. The term includes holding, storage, settling, and
aeration pits, ponds, or lagoons, but does not include
injection wells.
"Surface water" means all lakes, rivers, ponds, wetlands,
streams, inland waters, salt waters and all other surface
water and surface water courses within the jurisdiction of the
state of Washington.
"Tank" means a stationary device designed to contain an
accumulation of liquid or semisolid materials meeting the
definition of solid waste or leachate, and which is
constructed primarily of nonearthen materials to provide
structural support.
"Transfer station" means a permanent, fixed, supplemental
collection and transportation facility, used by persons and
route collection vehicles to deposit collected solid waste
from offsite into a larger transfer vehicle for transport to a
solid waste handling facility.
"Treatment" means the physical, chemical, or biological
processing of solid waste to make such solid wastes safer for
storage or disposal, amenable for recycling or energy
recovery, or reduced in volume.
"Twenty-five-year storm" means a storm of twenty-four
hours duration and of such intensity that it has a four
percent probability of being equaled or exceeded each year.
"Type 1 feedstocks" means source-separated yard and
garden wastes, wood wastes, agricultural crop residues,
wax-coated cardboard, preconsumer vegetative food wastes,
other similar source-separated materials that the
jurisdictional health department determines to have a
comparable low level of risk in hazardous substances, human
pathogens, and physical contaminants.
"Type 2 feedstocks" means manure and bedding from
herbivorous animals that the jurisdictional health department
determines to have a comparable low level of risk in hazardous
substances and physical contaminants when compared to a type 1
feedstock.
"Type 3 feedstocks" means meat and postconsumer
source-separated food wastes or other similar source-separated
materials that the jurisdictional health department determines
to have a comparable low level of risk in hazardous substances
and physical contaminants, but are likely to have high levels
of human pathogens.
"Type 4 feedstocks" means mixed municipal solid wastes,
postcollection separated or processed solid wastes, industrial
solid wastes, industrial biological treatment sludges, or
other similar compostable materials that the jurisdictional
health department determines to have a comparable high level
of risk in hazardous substances, human pathogens and physical
contaminants.
"Universal wastes" means universal wastes as defined in
chapter 173-303 WAC, Dangerous waste regulations. Universal
wastes include, but may not be limited to, dangerous waste
batteries, mercury-containing thermostats, and universal waste
lamps generated by fully regulated dangerous waste generators
or CESQGs.
"Unstable area" means a location that is susceptible to
forces capable of impairing the integrity of the facility's
liners, monitoring system or structural components. Unstable
areas can include poor foundation conditions and areas
susceptible to mass movements.
"Vadose zone" means that portion of a geologic formation
in which soil pores contain some water, the pressure of that
water is less than atmospheric pressure, and the formation
occurs above the zone of saturation.
"Vector" means a living animal, including, but not
limited to, insects, rodents, and birds, which is capable of
transmitting an infectious disease from one organism to
another.
"Vermicomposting" means the controlled and managed
process by which live worms convert organic residues into
dark, fertile, granular excrement.
"Waste tires" means any tires that are no longer suitable
for their original intended purpose because of wear, damage or
defect. Used tires, which were originally intended for use on
public highways that are considered unsafe in accordance with
RCW 46.37.425, are waste tires. Waste tires also include
quantities of used tires that may be suitable for their
original intended purpose when mixed with tires considered
unsafe per RCW 46.37.425.
"Wetlands" means those areas that are inundated or
saturated by surface or groundwater at a frequency and
duration sufficient to support, and under normal circumstances
do support, a prevalence of vegetation typically adapted for
life in saturated soil conditions. Wetlands generally include
swamps, marshes, bogs, and similar areas.
"Wood derived fuel" means wood pieces or particles used
as a fuel for energy recovery, which contain paint, bonding
agents, or creosote. Wood derived fuel does not include wood
pieces or particles coated with paint that contains lead or
mercury, or wood treated with other chemical preservatives
such as pentachlorophenol, copper naphthanate, or
copper-chrome-arsenate.
"Wood waste" means solid waste consisting of wood pieces
or particles generated as a by-product or waste from the
manufacturing of wood products, construction, demolition,
handling and storage of raw materials, trees and stumps. This
includes, but is not limited to, sawdust, chips, shavings,
bark, pulp, hogged fuel, and log sort yard waste, but does not
include wood pieces or particles containing paint, laminates,
bonding agents or chemical preservatives such as creosote,
pentachlorophenol, or copper-chrome-arsenate.
"Yard debris" means plant material commonly created in
the course of maintaining yards and gardens and through
horticulture, gardening, landscaping or similar activities.
Yard debris includes, but is not limited to, grass clippings,
leaves, branches, brush, weeds, flowers, roots, windfall
fruit, and vegetable garden debris.
"Zone of saturation" means that part of a geologic
formation in which soil pores are filled with water and the
pressure of that water is equal to or greater than atmospheric
pressure.
[Statutory Authority: Chapter 70.95 RCW. 05-11-033 (Order
04-12), § 173-350-100, filed 5/10/05, effective 6/10/05;
03-03-043 (Order 99-24), § 173-350-100, filed 1/10/03,
effective 2/10/03.]