Unless the context clearly requires otherwise, the definitions in this section apply throughout this chapter.

(1) "Active area" means that portion of a facility where ash disposal operations are being, are proposed to be, or have been conducted. Buffer zones are not considered part of the active area of a facility.

(2) "Aquifer" means a geologic formation, group of formations, or part of a formation capable of yielding a significant amount of groundwater to wells or springs.

(3) "Ash" means special incinerator ash.

(4) "Ash cell" or "cell" means an active disposal phase of the site which must be divided into a series of phases to minimize the active ash disposal area.

(5) "Beneficial use" means the water uses as defined by the water resources management program established by the Water Resources Act of 1971 and chapter 173-500 WAC.

(6) "Bottom ash" means ash residues remaining on the incineration or energy recovery facility grates or in the combustion chambers after combustion. Bottom ash may or may not be a special incinerator ash.

(7) "Buffer zone" means that part of a facility which lies between the active area and the property boundary.

(8) "Closure" means those actions taken by the owner or operator of an ash facility to cease disposal operations. A closure notice will be provided to the department with the exact date to ensure that all facilities are closed in conformance with applicable rules at the time of closure and to prepare the site for the post-closure period using best engineering practices.

(9) "Construction quality assurance plan" means a plan describing the methods by which the professional engineer in responsible charge of inspection of the project will determine that the facilities were constructed without significant change from the department approved plans and specifications.

(10) "Contaminate" means to discharge a substance into groundwater that would cause:

(a) The concentration of that substance in the groundwater to exceed the maximum contamination level specified in WAC 173-306-9901;

(b) A statistically significant increase in the concentration of that substance in the groundwater where the existing concentration of that substance exceeds the maximum contaminant level specified in WAC 173-306-9901; or

(c) A statistically significant increase above background in the concentration of a substance which:

(i) Is not specified in WAC 173-306-9901; and

(ii) Is present in the ash; and

(iii) Has been determined to present a substantial risk to human health or the environment in the concentration found at the point of compliance by the department in consultation with the department of health.

(11) "Critical habitat" means habitat defined as critical by the Endangered Species Act of 1973 (P.L. 93-205).

(12) "Department" means the department of ecology.

(13) "Department's approval" means an approval letter by the director after the review of all engineering reports, plans and specifications, and any other engineering documents by a registered engineer.

(14) "Director" means the director of the department of ecology or the director's designee.

(15) "Displacement" means the relative movement of any two sides of a fault measured in any direction.

(16) "Dispose" or "disposal" means the treatment, utilization, processing, or final deposit of special incinerator ash.

(17) "Disposal facility" means all structures, other appurtenances, improvements and land used for recycling, storing, treating, or disposing of special incinerator ash.

(18) "Domestic water" means any water used for human consumption, other domestic activities, livestock watering or for any use for which a water right has been granted.

(19) "Energy recovery" means the recovery of energy in a usable form from mass burning, fluidized bed 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.

(20) "Existing disposal facility" means a disposal facility that is owned or leased and in operation, or for which 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, rules, and ordinances.

(21) "Existing residential development" means any existing development of residential dwelling units with a density of at least one unit per acre and a total of more than ten dwellings at time of permit application.

(22) "Expanded disposal facility" means a disposal facility adjacent to an existing facility for which the land is purchased and approved by the department after the effective date of this chapter. The department shall consider a vertical expansion approved and permitted after the effective date of this chapter to be an expanded disposal facility.

(23) "Fault" means a fracture along which rocks or soils on one side have been displaced with respect to those on the other side.

(24) "Facility" means disposal facility.

(25) "Flyash" or "flyash/scrubber residue" means ash swept from the incineration or energy recovery facility combustion chamber and collected from the boilers, economizers, and air pollution control devices such as scrubbers, baghouses, and electro-static precipitators. Flyash or flyash/scrubber residues may or may not be special incinerator ash.

(26) "Generate" means any act or process that produces special incinerator ash or which first causes special incinerator ash to become subject to regulation.

(27) "Generator" means any incineration facility owner/operator who generates a special incinerator ash. An existing generator is any generator whose facility is in operation on the effective date of this chapter.

(28) "Holocene" means the most recent measure of geologic time period extending from the end of the Pleistocene period to the present.

(29) "Incineration" means reducing the volume of solid wastes by use of an enclosed device that uses controlled flame combustion.

(30) "Independent third party" means, for the purpose of liner construction, a person, approved by the department, with demonstrated experience in successful liner installation or inspection, who is financially and organizationally independent of:

(a) The generator or facility owner/operator;

(b) The raw material producer (such as the resin manufacturer or the bentonite producer);

(c) The liner manufacturer;

(d) The liner installer; or

(e) Any other person who might have a financial or organizational connection to the facility.

(31) "Land treatment" means the practice of applying ash waste onto or incorporating into the soil surface. If the waste will remain after the facility is closed, this practice is disposal.

(32) "Management" means the handling, storage, collection, transportation, and disposal of special incinerator ash.

(33) "Monofill" means a disposal facility or part of a facility, that is not a land treatment facility, at which only special incinerator ash is finally deposited in or on.

(34) "New disposal facility" means a facility that begins operation or construction after the effective date of this chapter.

(35) "One hundred-year flood" means a flood that has a one percent chance of being equalled or exceeded in any given year.

(36) "Perennial surface water bodies" are normally continuous bodies of water with natural flows throughout the year and includes lakes, rivers, ponds, irrigation canals, streams, reservoirs, inland waters, salt waters, and all other waters of the state (not to include man-made lagoons or impoundments for waste treatment or storage) within the jurisdiction of the state of Washington as defined by chapter 90.48 RCW, the Water Pollution Control Act.

(37) "Permeability" means the ability with which a porous material allows liquid or gaseous fluids to flow through it.

(38) "Permit" means a special incinerator ash disposal permit.

(39) "Person" means any person, firm, association, county, public, municipal, or private corporation, agency, or other entity whatsoever.

(40) "Pile" means any noncontainerized accumulation of ash that is used for treatment or utilization.

(41) "Plans and specifications" means the detailed drawings and specifications used in the construction or modification of ash disposal facilities.

(42) "Point of compliance" means that part of groundwater which lies beneath the perimeter of a disposal facility's active area as that active area would exist at the closure of the facility.

(43) "Post-closure" means the requirements placed upon disposal facilities after closure to ensure their environmental safety for a thirty-year period or until the site becomes stabilized (i.e., cap integrity maintained, little or no settlement or leachate generation).

(44) "Processing" means an operation to convert ash into a useful product or to prepare it for disposal.

(45) "Reclamation" means to process an ash waste in order to recover usable products.

(46) "Utilization" means consuming, expending, exhausting or using an ash waste.

(47) "Sole source aquifer" means an aquifer designated by the Environmental Protection Agency under section 1424e of the Safe Drinking Water Act (P.L. 93-523).

(48) "Solid waste" means all putrescible and nonputrescible solid and semisolid wastes, including but not limited to garbage, rubbish, ashes, industrial wastes, swill, demolition and construction wastes, abandoned vehicles or parts thereof, and recyclable commodities. This includes all liquid, solid, and semisolid materials that are not the primary products of public, private, industrial, commercial, mining, and agricultural operations. Solid waste includes, but is not limited to, sludge from wastewater treatment plants, septage from septic tanks, woodwaste, dangerous waste, and problem wastes.

(49) "Special incinerator ash" means ash residues that result from the operation of incineration or energy recovery facilities managing municipal solid waste from residential, commercial, and industrial establishments, if the ash residues (a) would otherwise be regulated as hazardous wastes under chapter 70.105 RCW; and (b) are not regulated as a hazardous waste under the Federal Resource Conservation and Recovery Act, 42 U.S.C. Sec 6901 et seq.

(50) "Spill" means any accidental discharges or overflow of fluids or processed water from contained areas or holding tanks to floor drains or a municipal sewer system.

(51) "Stabilization" or "solidification" means a technique that limits the solubility and mobility of waste constituents. Solidification immobilizes a waste through physical means and stabilization immobilizes a waste by bonding or chemically reacting with the stabilizing material.

(52) "Storage" means the temporary holding (no longer than forty-five days from date of production) of a limited amount (not to exceed thirty days worth of daily production) of special incinerator ash.

(53) "Subsidence" means a sinking of the land surface due to the removal of solid mineral matter or fluids from the subsurface.

(54) "Surface impoundment" means a facility or part of a facility that 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) 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.

(55) "Treatment" means those engineered physical or chemical processes to make special incinerator ash safer for transport, amenable for energy or material resource recovery, amenable for storage or disposal, or reduced in volume.

(56) "Unstable slopes" means any area where the mass movement of earthen materials i.e., landslides, rockfalls, mudslides, slumps, earth flows, or debris flow is likely to occur.

(57) "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.