LAST REVISED 07/11/89          
          RULE 1.2  Definitions

          Except  as  otherwise  specifically  provided in these rules and,
          except where the context otherwise indicates, words used in these
          rules are used in exactly the same sense  as  the  same words are
          used in the Health and Safety Code.

          A1 Actual Emission Reductions
              A reduction in allowable emissions from the stationary source
              selected  for  emission  offsets,  from  a baseline which  is
              representative of normal operations approved  by  the Control
              Officer. This baseline must be based on the average of actual
              emissions from the three years operation immediately prior to
              the  submission  of  the  complete  application.  The Control
              Officer may approve any other time period, within five  years
              prior  to the date of application that is more representative
              of normal source operation.

          A2 Affected Pollutant
              An air pollutant  for  which  an ambient air quality standard
              has  been  established by the EPA  and/or  the  ARB  and  the
              precursors to  such  pollutants.  Also  those  air pollutants
              which the EPA, and ARB of the District, after public  hearing
              determine  may  have  a  significant  adverse  effect  on the
              environment, public health or public welfare.

          A3 Agricultural Burning
              Open  outdoor  fires  used  in agricultural operations in the
              growing  of  crops  or raising of  fowl  or  animals,  forest
              management,    range   improvement,    wildland    vegetative
              management, the  improvement  of  land  for wildlife and game
              habitat, disease or pest prevention or the  maintenance  of a
              system for delivery of water used in agricultural operations.

          A4 Air Contaminant or Air Pollutant
              Any   discharge,  release,  or  other  propagation  into  the
              atmosphere  and  includes,  but  is  not  limited  to, smoke,
              charred  paper,  dust,  soot,  grime,  carbon,  fumes, gases,
              odors, particulate matter, acids, or any combination thereof.

          A5 Air Quality Increment
              An  increment  of  allowable air quality degradation,  beyond
              baseline, as established  in the Clean Air Act Section 163(b)
              or,  for  pollutants  for  which   no   increment   has  been
              established  pursuant  to the Clean Air Act, an increment  of
              allowable  air  quality degradation  as  established  by  the

              In establishing air  quality  increments,  the District shall
              take   into   consideration   the  impact  of  emissions   on
              neighboring areas.

          A6 Ambient Air Quality Standards
              Unless  otherwise specifically stated,  ambient  air  quality
              standards  shall  be  interpreted  to  be  federal  and state
              ambient  air  quality standards. For the purpose of submittal
              to the Environmental  Protection  Agency for the inclusion in
              State Implementation Plan, all references in this rule are to
              Ambient Air Quality Standards.

          A7 Approved Combustibles
              Paper,  cardboard,  wood,  dry  vegetative  matter  or  other
              materials as approved by the Control Officer.

          A8 Atmosphere
              The air that envelopes or surrounds the earth.

          A9 ARB
              The California Air Resources Board.

          B1 Baseline Air Quality; Date
              The ambient concentration level reflecting actual air quality
              as monitored or modeled as of May 5, 1979.

          B2 Best Available Control Technology (BACT)
              For any stationary source, the more stringent of:
              1. The  most  effective  emission  control  device,  emission
                 limit, or technique which has been  required  or  used for
                 the  type  of equipment comprising such stationary source,
                 unless the applicant  demonstrates  to the satisfaction of
                 the  Control  Officer  that  such  limitations   are   not
                 achievable; or
              2. Any  other emission control device or technique determined
                 to be  technologically  feasible and cost effective by the
                 Control  Officer. Under no  circumstances  shall  BACT  be
                 determined  to be less stringent than the emission control
                 required by any  applicable  provision of District, State,
                 or  Federal  laws  or regulations,  unless  the  applicant
                 demonstrates to the  satisfaction  of  the Control Officer
                 that such limitations are not achievable.

          B3 Board
              The  Air Pollution Control Board of the Siskiyou  County  Air
              Pollution Control District which is the Board of Supervisors.

          B4 Bulk Plant
              Any facility  where  petroleum  products are received by tank
              car or tank vehicle and are stored or blended in bulk for the
              purpose of distribution in tank car or tank vehicle.

          C1 Cargo Carriers
              Trains dedicated to a specific stationary source.

          C2  Class I Area
              Any area which has been or may be  designated  Class  I  by a
              Federal   or   State   authority   empowered   to  make  such

          C3  Class I Impact Area
              All  lands within the District, located within 10  kilometers
              of any Class I area.

          C4 Cogeneration
              The sequential use of energy for the production of electrical
              and useful  thermal  energy.  The sequence can be thermal use
              followed by power production or  the  reverse, subject to the
              following standards:
             1.  At least five (5) percent of the facility's  total  annual
                 energy  output  shall  be  in  the  form of useful thermal
             2.  Where useful thermal energy follows power  production, the
                 thermal energy output is not less than 42.5 percent of any
                 natural gas and oil energy input.

          C5 Combustible Waste
              Any  solid  or  liquid combustible waste material  containing
              carbon in a free or combined state.

          C6 Combustion Contaminants
              Particulate matter  discharged  into  the atmosphere from the
              burning of any kind of material containing  carbon  in a free
              or combined state.

          C7 Complete Application
              Completeness  of an application for an authority to construct
              a new or modified stationary source shall be evaluated on the
              basis of a list  of  required information shown in Appendix A
              of these regulations.

          C8 Condensed Fumes
              Minute, solid particles  generated  by  the  condensation  of
              vapors from solid matter after volatilization from the molten
              state,  or  may  be  generated by sublimation, distillations,
              calcination,  or  chemical  reaction,  when  these  processes
              create air-borne particles.

          C9 Contiguous Property
              Two  or more parcels  of  land  with  a  common  boundary  or
              separated   solely  by  a  public  roadway  or  other  public

          C10Control Officer
              An Air Pollution  Control  Officer of the Siskiyou County Air
              Pollution Control District.

          C11 Cost-Effective
              A cost per unit of emissions reduction which is lower than or
              equivalent to the maximum unit  costs  of  the  same emission
              reduction through the use of demonstrated BACT calculated  in
              current year dollars.

          D1 District
              The Siskiyou County Air Pollution Control District.

          D2 Dusts
              Minute,  solid  particles  released  into  the air by natural
              forces or by mechanical processes such as crushing, grinding,
              milling,   drilling,   demolishing,   shoveling,   conveying,
              covering, bagging, sweeping, or other similar processes.

          E1 EPA
              The   United   States  Environmental  Protection  Agency,  as
              established by Title 40 of the Code of Federal Regulations.

          F1 Federal Land Manager
              The Secretary of  the  Department  with  authority  over  the
              specified federal lands.

          F2 Fugitive Emissions
              Emissions  which  could  not reasonably pass through a stack,
              chimney, vent or other functionally equivalent opening.

          G1 Good Engineering Practice
              The height necessary to ensure that emissions from a stack do
              not result in excessive concentrations of any air contaminant
              in the immediate vicinity of the source.

          H1 Halogenated Hydrocarbons
              1,1,1-trichloroethane,          methylene           chloride,
              trichlorfluoromethane    (CFC-11),    dichlorodifluoromethane
              (CFC-12),  chlorodifluoromethane  (CFC-22),  trifluoromethane
              (CFC-23),         trichlorotrifluoroethane         (CFC-113),
              dichlorotetrafluoroethane    (CFC-114),    and   chloropenta-
              fluoroethane (CFC-115).

          H2 Hearing Board
              The  Hearing  Board  of  the  Siskiyou  County Air  Pollution
              Control District.

          I1 Impact Analysis
              An  air  quality modeling analysis used to  estimate  maximum
              ground  level   impacts  of  a  source  for  total  suspended
              particulates, carbon  monoxide,  oxides of sulfur, and oxides
              of nitrogen assuming one hundred (100)  percent conversion of
              nitrogen  oxides into NO2 and calculating  all  emissions  of
              sulfur oxides as SO2 .

          I2 Implement of Husbandry
              A  vehicle which  is  used  exclusively  in  the  conduct  of
              agricultural  operations, and which is not designed primarily
              for the transportation of persons or property on a highway.

          I3 Incinerator
              Any furnace or similar enclosed fire-chamber, with or without
              a draft control,  used  for  burning  refuse  or  other waste

          M1 Major Source
              Any  stationary source which directly emits one hundred  tons
              per year or more of any air pollutant.

          M2 Modification
              Any physical  change,  change  in  method of operation of, or
              addition to an existing stationary source,  or  any change in
              hours of operation or production rate which would necessitate
              a   change   in   permit   conditions,  except  that  routine
              maintenance or repair shall  not  be  considered  a  physical
              change. Unless previously limited by a permit condition,  the
              following  shall  not  be  considered  changes  in  method of
             1.  An  increase in the production rate if such increase  does
                 not exceed  the  operating  design  capacity or the actual
                 demonstrated capacity of the stationary source as approved
                 by the Control Officer.
             2.  A change in ownership.
             3.  A replacement of a piece of equipment  with  an  identical
                 piece  of  equipment with emissions less than or equal  to
                 those from the original piece of equipment.

          M3 Multi-Component System
              A collection, or combination, of mutually dependent articles,
              structures, or  devices  customarily  or necessarily started,
              operated and taken out of service as a unit.

          M4 Multiple-Chamber Incinerator
              Any article, machine, equipment, contrivance,  structure,  or
              any part of a structure used to dispose of combustible refuse
              by  burning;  consisting  of  three  or more refractory-lined
              chambers in series; physically separated by refractory walls;
              interconnected by gas passage ports or  ducts;  and employing
              adequate  design parameters necessary for maximum  combustion
              of the material to be burned.

          N1 Net Air Quality Benefit
              A  net improvement  in  air  quality  resulting  from  actual
              emission  reductions impacting the same general area affected
              by the new or modified source.

          N2 Net Emissions Increase
              The sum of  all increases in emissions of any given pollutant
              from a new or  modified stationary source occurring after the
              baseline date, minus  any  reduction  in  emissions  of  that
              pollutant at the stationary source occurring five years prior
              to  the baseline date. Reductions in emissions shall be valid
              for determining  net  emissions  increases  only  if they are
              established pursuant to Authorities to Construct and  Permits
              to Operate.

          O1 Open Outdoor Fire
              Complete  or partial burning or smoldering of any combustible
              refuse or other material of any type, directly exposed to the
              atmosphere,   whether   or   not  enclosed  in  a  fire-proof
              container, where the products of combustion are not channeled
              through a flue.

          P1 Particulate Matter
              Any material, except uncombined  water,  which  exists  in  a
              finely  divided  form  as  a  liquid  or  solid  at  standard

          P2 Permit
              A   Certificate   of   Compliance,  Authority  to  Construct,
              Temporary Permit to Operate,  or Permit to Operate, whichever
              is legally in effect.

          P3 Person
              Any  person,  firm,  association  organization,  partnership,
              business trust, corporation, company,  contractor,  supplier,
              installer,  user or owner, or any state or local governmental
              agency or public district or any officer or employee thereof.

          P4 PM10
              Particulate matter that includes only those particles with an
              aerodynamic diameter  less  than  or  equal  to  a nominal 10

          P5 Portable Source
              A source which has been permitted and is relocated  from time
              to time.

          P6 Potential to Emit
              The  maximum  capacity of a stationary source to emit an  air
              pollutant under  its  physical  or  operational design, after
              considering  physical  or  operational limitations  that  are
              enforceable by permit conditions.

          P7 Precursor
              A  directly emitted pollutant  that,  when  released  to  the
              atmosphere,  forms  or  causes to be formed or contributes to
              the formation of a secondary  pollutant  for which an ambient
              air quality standard has been adopted, or  whose  presence in
              the  atmosphere  will contribute to the violation of  one  or
              more ambient air quality standards.

          P8 Process
              For any stationary  source, separate items of equipment shall
              be considered as part of the same process if the operation of
              each item of equipment  is  dependent  upon  or  affects  the
              operation  of  the  others  and  the  operation  of  all such
              equipment involves a common raw material or product.

          P9 Process Weight
              The  total  weight  of  all  materials  introduced  into  any
              specific   process   which   may  cause  discharge  into  the
              atmosphere. Solid fuels charged will be considered as part of
              the  process  weight,  but  liquid   and  gaseous  fuels  and
              combustion air will not. The weight of wood products shall be
              calculated at 12% moisture on a dry basis.

          P10Process Weight Rate
              Total process weight divided by the number  of  hours  in one
              complete  operation, from the beginning to completion of  any
              given process,  excluding any time during which the equipment
              is idle.

          P11PSD Permit
              A Permit to Operate  issued  pursuant  to  Section 105 of the
              Federal Clean Air Act.

          R1 Reactive Organic Compound
              Any  volatile  compound  containing carbon except:   methane,
              carbon  monoxide,  carbon dioxide,  carbonic  acid,  metallic
              carbides or carbonates,  ammonium carbonates, and halogenated

          R2 Reconstructed Source
              Any source undergoing reconstruction  where the fixed capital
              cost of the new components exceeds 50 percent  of  the  fixed
              capital  cost of a comparable entirely new stationary source.
              Fixed capital  cost  means  the capital needed to provide all
              the depreciable components. A  reconstructed  source shall be
              treated as a new stationary source.
          R3 Regulation
              One of the major subdivisions of rules of the Siskiyou County
              Air Pollution Control District.

          R4 Residential Rubbish
              Refuse  originating  from  residential  uses including  wood,
              paper,  cloth,  cardboard,  tree  trimmings,   leaves,   lawn
              clippings, and dry plants.

          R5 Resource Recovery Project
              A project which would convert liquid or solid waste in such a
              manner as to produce energy as a by-product.

          R6 Rule
              A rule of the Siskiyou County Air Pollution Control District.

          S1 Seasonal Source
              Any  source with more than 75 percent of its annual emissions
              within a consecutive 90-day period.

          S2 Section
              A section  of  the  Health  and  Safety  Code of the State of
              California   unless   some   other  statute  is  specifically

          S3 Shall and May
             "Shall" is mandatory; "May" is permissive.

          S4 Significance Level
              The potential of a new or modified  stationary source to emit
              air  contaminants  that  would equal or  exceed  any  of  the
              following rates:

                             POLLUTANT                   TONS/YEAR
                         Halogenated Hydrocarbons           40
                         Reactive Organic Compounds         40
                         Nitrogen Oxides                    40
                         Sulfur Oxides                      40
                         Particulate Matter                 25
                         Carbon Monoxide                   100
                         Lead                                0.6
                         Asbestos                            0.007
                         Beryllium                           0.0004
                         Mercury                             0.1
                         Vinyl Chloride                      1
                         Fluorides                           3
                         Sulfuric Acid Mist                  7
                         Hydrogen Sulfide                   10
                         Total Reduced Sulfur Compounds     10
                         Reduced Sulfur Compounds           10
                         PM10                               15

          Furthermore,  significance level  also  means  any  net  emission
          increase from any  new  or modified stationary source which would
          be constructed within 10 kilometers of a Class I area and have an
          air quality impact on such  an  area  equal  to or greater than 1
          microgram per cubic meter (24-hour average).

          S5 Source Operation
              The  last  operation  preceding  the  emission   of   an  air
              contaminant which operation:
             1.  Results  in  the  separation  of air contaminants from the
                 process  materials  or in the conversion  of  the  process
                 materials  into  air  contaminants,  as  in  the  case  of
                 combustion of fuels.
             2.  Is not an air pollution abatement operation.
          S6 Standard Conditions
              Dry gas temperature of 68  degrees  Fahrenheit  and  dry  gas
              pressure  of 14.7 pounds per square inch absolute. Results of
              all analyses  and  tests  shall be calculated and reported at
              this gas temperature and pressure.

          S7 Stationary Source
              Any  building,  structure, facility,  or  installation  which
              emits  or  may  emit   any  affected  pollutant.  "Building",
              "structure", or "facility"  includes  all  pollutant-emitting
              activities,  including  activities  located adjacent  to  the
              District boundaries which:
             1.  Belong to the same industrial grouping, and
             2.  Are  located  on  one  or  more  contiguous   or  adjacent
                 properties and
             3.  Are  under  the  same  or common ownership, operation,  or
                 control or which are owned  or  operated by entities which
                 are under common control.
              Pollutant-emitting activities shall  be considered as part of
              the same industrial grouping if:
              1. They  belong  to  the  same two-digit standard  industrial
                 classification code, or
              2. They  are  part of a common  production  process.  (Common
                 production   process    includes   industrial   processes,
                 manufacturing  processes,   and  any  connected  processes
                 involving  a common raw material.)  The  emissions  within
                 District boundaries  from  cargo  carriers  dedicated to a
                 specific stationary source, shall be considered  emissions
                 from the stationary source.

          T1 Total Reduced Sulfur (TRS)
              Reduced  sulfur  contained  in  hydrogen sulfide, mercaptans,
              dimethyl sulfide, dimethyl disulfide or other organic sulfide
              compounds, all expressed as hydrogen sulfide. Sulfur dioxide,
              sulfur trioxide, or sulfuric acid  are  not to be included in
              the determination of TRS.

          T2 Trade Secrets
              May  include but not limited to any formula,  plan,  pattern,
              process,  tool,  mechanism,  compound,  procedure, production
              data, or compilation of information which  is  not  patented,
              which   is   known  only  to  certain  individuals  within  a
              commercial concern who are using it to fabricate, produce, or
              compound an article  of  trade or a service having commercial
              value, and which gives its  user  an  opportunity to obtain a
              business advantage over competitors who  do  not  know or use

          V1 Variance
              An  authorization  by  the  Hearing Board to permit some  act
              contrary to the requirements  specified  by  these  rules and

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