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Arkansas SIP: Regulation of Plan § 3. Definitions

Regulatory Text:
SECTION 3. DEFINITIONS

(Approved by EPA 10/05/76 (41 FR 43904) at 52.170(c)(04) effective 10/05/76. Revisions approved by EPA 02/23/89 (54 FR 07764) at 52.170(c)(26) effective 03/27/89; and 05/01/89 (54 FR 18494) at 52.170(c)(27) effective 06/30/89.)

   When used in these Regulations of the Plan:

   (a) "Arkansas Air Pollution Control Code" means rules and regulations adopted by the Department of Pollution Control and Ecology of the State of Arkansas, as amended from time to time, pursuant to and in furtherance of the Act. Provisions of the Arkansas Air Pollution Control Code shall not be considered a part of the Plan except for those provisions specifically described in the Plan.

   (b) "Commission" means the Commission on Pollution Control and Ecology of the State of Arkansas.

   (c) "Department" means the Department of Pollution Control and Ecology of the State of Arkansas. When reference is made in these Regulations to actions taken by or with reference to the Department, the reference is to the staff of the Department acting at the direction of the Commission.

   (d) "Director" means the director of the Department of Pollution Control and Ecology, acting directly or through the staff of the Department.

   (e) "Equipment" means any device, except equipment used for any mode of transportation, capable of causing the emission of an air contaminant into the open air, and any stack, conduit, flue, duct, vent or similar device connected to or attached to, or serving the equipment.

   (f) "Equipment used in a manufacturing process" means equipment, the primary object of which is the treatment and/or conversion of input materials to produce a salable or usable end product.
   (g) "Flue" or "stack" means any conduit or duct arranged to conduct an effluent to the open air.

   (h) "Incinerator" means all devices by which garbage, refuse, or other combustible material is reduced in volume by a combustion process in which the fuel/air ratio is or can be controlled so that the remaining solid residues contain little or no combustible material.

   (i) "Opacity" means the state of a substance which renders it partially or wholly impervious to rays of light so that the substance partially or wholly obscures an observer's view.

   (j) "Potential emission rate" means the total weight rate at which particulate matter is, or in the absence of an air cleaning device would be, emitted from an air contamination source when such source is operated at its maximum rated capacity. The potential emission rate may be determined by sampling in a flue, prior to the inlet of the air cleaning device, or by estimating the weight rate of emissions by performing a "material balance" (difference between process input weight and output weight) for the process or operation, or by estimating the weight rate of emissions using estimating techniques approved by the Commission. When a number of air contamination sources (each of which is capable of being operated individually) are manifolded together so that their emissions are discharged to a single flue, the potential emission rate and allowable emission rate for each source shall be determined individually.

   (k) "Smoke" means finely divided particulate matter resulting from incomplete combustion, consisting primarily of carbon and other combustible material.

   (l) "Standard Smoke Chart" means the Ringlemann Chart, as published by the U.S. Bureau of Mines in Information Circular 8333, dated May, 1967, photographically reduced to 1/18th in size for use in the field, or any method or device for grading smoke judged by the Department to be equivalent to the Ringlemann Chart.  

   (m) "Standard conditions" means at a temperature of 20 degrees Centigrade and a pressure of 760 millimeters of mercury.

   (n) "Existing equipment" means equipment which was placed in operation prior to September 1, 1975 or for which a permit has been issued by the Department prior to September 1, 1975.  

   (o) "New equipment" means all equipment other than existing equipment as defined herein.

   (p) "Construction" means fabrication, erection or installation of equipment.

   (q) "Modification" means any physical change in, or change in the method of operation of, a stationary source which increased the emission rate of any pollutant for which a national standard has been promulgated by Environmental Protection Agency or which results in the emission of any such pollutant not previously emitted, except that:
     (i) Routine maintenance, repair, and replacement shall not be considered a physical change, and
     (ii) The following shall not be considered a change in the method of operation.
       (A) An increase in the production rate, if such increase does not exceed the operating design capacity of the source;
       (B) An increase in the hours of operations;
       (C) Use of an alternative fuel or raw material, if
prior to the effective date of a section of these regulations which imposes conditions or limits modifications, the source is designed to accommodate such alternative use.

   (r)   (i) "Dispersion technique" means any technique which attempts to affect the concentration of a pollutant in the ambient air by:  
       (A) Using that portion of a stack which exceeds good engineering practice stack height;
       (B) Varying the rate of emission of a pollutant according to atmospheric conditions or ambient concentrations of that pollutant; or
       (C) Increasing final exhaust gas plume rise by  manipulating source process parameters, exhaust gas parameters, stack parameters, or combining exhaust gases from several existing stacks into one stack; or other selective handling of exhaust gas streams so as to increase the exhaust gas plume rise.
     (ii) The preceding sentence does not include:  
       (A) The reheating of gas stream, following use of a pollution control system, for the purpose of returning the gas to the temperature at which it was originally discharged from the facility generating the gas stream;
       (B) The merging of exhaust gas streams where:
         (1) The source owner or operator demonstrates that the facility was originally designed and constructed with such merged gas streams;  
         (2) After July 8, 1985, such merging is part of a change in operation at the facility that includes the installation of pollution controls and is accompanied by a net reduction in the allowable emissions of a pollutant. This exclusion from the definition of "dispersion techniques" shall apply only to the emission limitation for the pollutant affected by such change in operation; or
         (3) Before July 8, 1985, such merging was part of a change in operation at the facility that included the installation of emissions control equipment or was carried out for sound economic or engineering reasons. Where there was an increase in the emission limitation or, in the event that no emission limitation was in existence prior to the merging, an increase in the quantity of pollutants actually emitted prior to the merging, the reviewing agency shall presume that merging was significantly motivated by an intent to gain emissions credit for greater dispersion. Absent a demonstration by the source owner or operator that merging was not significantly motivated by such intent, the reviewing agency shall deny credit for the effects of such merging in calculating the allowable emissions for the source;
       (C) Smoke management in agricultural or silvicultural prescribed burning programs;
       (D) Episodic restrictions on residential woodburning and open burning; or
       (E) Techniques under Subsection (r)(i)(C) which increase final exhaust gas plume rise where the resulting allowable emissions of sulfur dioxide from the facility do not exceed 5,000 tons per year.

   (s) "Good engineering practice" (GEP) stack height means the greater of:
     (i) 65 meters, measured from the ground-level elevation at the base of the stack:
     (ii)   (A) For stacks in existence on January 12, 1979, and for which the owner or operator had obtained all applicable permits or approvals required under 40 CFR Parts 51 and 52,
Hg = 2.5H,
provided the owner or operator produces evidence that this equation was actually relied on in establishing an emission limitation;
       (B) For all other stacks,
Hg = H + l.5L,
where
Hg = good engineering practice stack height, measured from the ground-level elevation at the base of the stack,
H = height of nearby structure(s) measured from the ground-level elevation at the base of the stack,
L = lesser dimension, height or projected width, of nearby structure(s)
provided that the EPA or Director may require the use of a field study or fluid model to verify GEP stack height for the source; or
     (iii) The height demonstrated by a fluid model or a field study approved by the EPA or Director, which ensures that the  emissions from a stack do not result in excessive concentrations of any air pollutant as a result of atmospheric downwash, wakes, or eddy effects created by the source itself, nearby structures or nearby terrain features.

   (t) "Nearby" as used in Subsection (s) of this section is defined for a specific structure or terrain feature; and
     (i) for purposes of applying the formulae provided in Subsection (s)(ii) means that distance up to five times the lesser of the height or the width dimension of a structure, but not greater than 0.8 km (½ mile), and
     (ii) for conducting demonstrations under Subsection (s)(iii) means not greater than 0.8 km (½ mile), except that the portion of a terrain feature may be considered to be nearby which falls within a distance of up to 10 times the maximum height (Ht ) of the feature, not to exceed 2 miles if such feature achieves a height (Ht ) 0.8 km from the stack that is at least 40 percent of the GEP stack height determined by the formulae provided in Subsection (s)(ii)(B) of this part or 26 meters, whichever is greater, as measured from the ground level elevation at the base of the stack. The height of the structure of terrain feature is measured from the ground level elevation at the base of the stack.

   (u) "Excessive concentration" is defined for the purpose of determining good engineering practice stack height under Subsection (s)(iii) and means:
     (i) for sources seeking credit for stack height exceeding that established under Subsection (s)(ii), a maximum ground-level concentration due to emissions from a stack due in whole or part to downwash, wakes, and eddy effects produced by nearby structures or nearby terrain features which individually is at least 40 percent in excess of the maximum concentration experienced in the absence of such downwash, wakes, or eddy effects and which contributes to a total concentration due to emissions from all sources that is greater than an ambient air quality standard. For sources subject to the prevention of significant deterioration program, an excessive concentration alternatively means a maximum ground-level concentration due to emissions from a stack due in whole or part to downwash, wakes, or eddy effects produced by nearby structures or nearby terrain features which individually is at least 40 percent in excess of the maximum concentration experienced in the absence of such downwash, wakes, or eddy effects and greater than a prevention of significant deterioration increment. The allowable emission rate to be used in making demonstrations under this part shall be prescribed by the New Source Performance Standard that is applicable to the source category unless the owner or operator demonstrates that this emission rate is infeasible. Where such demonstrations are approved by the Director, an alternative emission rate shall be established in consultation with the source owner or operator;
     (ii) for sources seeking credit after October 11, 1983, for increases in existing stack heights up to the heights established under Subsection (s)(ii), either
       (a) a maximum ground-level concentration due in whole or part to downwash, wakes, or eddy effects as provided in paragraph (u)(i) of this subsection, except that the emission rate specified by the State Implementation Plan (or, in the absence of such a limit, the actual emission rate) shall be used, or
       (b) the actual presence of a local nuisance caused by the existing stack, as determined by the Director; and
     (iii) for sources seeking credit after January 12, 1979 for a stack height determined under Subsection (s)(ii) where the Director requires the use of a field study or fluid model to verify GEP stack height, for sources seeking stack height credit after November 9, 1984, based on the aerodynamic influence of cooling towers, and for sources seeking stack height credit after December 31, 1970, based on the aerodynamic influence of structures not adequately represented by the equations in Subsection (s)(ii), a maximum ground-level concentration due in whole or part to downwash, wakes, or eddy effects that is at least 40 percent in excess of the maximum concentration experienced in the
absence of such downwash, wakes, or eddy effects.

   (v) "Major modification" means any physical change in or change in the method of operation of a major stationary source that would result in a significant net emission increase of any pollutant subject to regulation under the Clean Air Act.

   (w) "Emission limitation" and "emission standards" means a requirement established by the Director or the EPA which limits the quantity, rate or concentration of emission of air pollutants on a continuous basis, including any requirements which limit the level of opacity, prescribe equipment, set fuel specifications, or prescribe operation or maintenance procedures for a source to assure continuous emission reduction.

   (x) "Stack" means any point in a source designed to emit solids, liquids or gases into the air, including a pipe or duct but not including flares.

   (y) "Stack in existence" means that the owner or operator had
     (1) begun, or caused to begin, a continuous program of physical on-site construction of the stack or
     (2) entered into binding agreements or contractual obligations, which could not be cancelled or modified without  substantial loss to the owner or operator, to undertake a program of construction of the stack to be completed in a reasonable time.

   (z) "National Ambient Air Quality Standard, "Primary National Ambient Air Quality Standard", and "Secondary National Ambient Air Quality Standard" mean those primary and secondary National Ambient Air Quality Standards promulgated by the United States Environmental Protection Agency in 40 CFR 50.1 through 50.11, as in effect on July 31, 1987, which are hereby incorporated herein by reference.

   (aa) "Air quality increment" means any maximum allowable increase in pollutant concentration over the baseline concentration (ambient air increment) listed in 40 CFR 52.21(c) or 52.21(p), as in effect on July 31, 1987, which are hereby incorporated herein by reference.

   (bb) "Particulate matter" means any airborne finely divided solid or liquid material with an aerodynamic diameter smaller than 100 micrometers.  

   (cc) "Particulate matter emissions" means all finely divided solid or liquid material, other than uncombined water, emitted to the ambient air as measured by applicable reference methods, or an equivalent or alternative method, specified in Appendix A of 40 CFR Part 60, or by a test method specified in these regulations or any supplement thereto.

   (dd) "PM10" means particulate matter with an aerodynamic diameter less than or equal to a nominal 10 micrometers as measured by a reference method based on Appendix J of 40 CFR Part 50, or by an equivalent method designated in accordance with 40 CFR Part 53.

   (ee) "PM10 emissions" means finely divided solid or liquid material, with an aerodynamic diameter less than or equal to a nominal 10 micrometers emitted to the ambient air as measured by an applicable reference method, or an equivalent or alternative method, specified in 40 CFR Part 52, or by a test method specified in these regulations or any supplement thereto.

   (ff) "Total suspended particulate" means particulate matter as measured by the method described in Appendix B of 40 CFR Part 50, as in effect on July 31, 1987.  

Unless manifestly inconsistent therewith, other words and phrases used in these regulations shall have the same meaning used in the Act.