SAN DIEGO COUNTY AIR POLLUTION CONTROL DISTRICT
 
 
 
NOTE: The following listed sections and subsections will not be submitted to the federal Environmental Protection Agency (EPA) for inclusion in the San Diego State Implementation Plan (SIP):  Subsections (d)(1)(i), (d)(2)(iii) and (d)(5)(i). Subsections (d)(2)(i), (d)(2)(ii), and (d)(2)(iv) will be submitted to EPA for inclusion in the SIP only with respect to national ambient air quality standards. 
 

RULE 20.4. NEW SOURCE REVIEW - PORTABLE EMISSION UNITS

(Adopted & Effective: 5/17/94; Rev. Effective 12/17/97)
 

(a) APPLICABILITY

This rule applies to any new or modified portable emission unit.

(b) EXEMPTIONS

The exemptions contained in Rule 20.1, Section (b) apply to this rule. In addition, the provisions of this rule shall not apply to any previously permitted portable emission unit, unless such unit is modified.

Emission increases resulting from an air contaminant emission control project to reduce emissions from a portable emission unit shall be exempt from the emission offset requirements of Subsection (d)(5) of this rule to the extent that the project does not include an increase in the capacity of the emission unit being controlled. Emission increases that are associated with an increase in capacity of the emission unit being controlled shall be subject to the emission offset provisions of this rule, as applicable.

(c) DEFINITIONS

The definitions contained in R ule 20.1, Section (c) shall apply to this rule. In addition, for purposes of this rule, the following definitions shall apply.
 

  1.  "Initial Permit Issuance" means the first instance an Authority to Construct is issued for an emission unit pursuant to Rules 20.1 and 20.4, as they are currently in effect.
  2. "Previously Permitted" means a portable emission unit which has a valid Authority to Construct or Permit to Operate issued pursuant to these rules and regulations prior to May 17, 1994 and that the emission unit has not been modified since May 17, 1994 or otherwise undergone initial permit issuance.
  3. "Type I Portable Emission Unit" means a portable emission unit that can be operated only at stationary sources which have an aggregate potential to emit of less than 15 tons per year of oxides of nitrogen (NOx) and volatile organic compounds (VOC) and less than 100 tons per year of carbon monoxide (CO). Type I portable emission units may also operate at stationary sources which have an aggregate potential to emit greater than these levels if emission offsets at the ratios specified for Type II portable emission units in Table 20.4 - 2 are provided for the period of time the portable emission unit is located at such a stationary source. The limitation on operating at stationary sources which have an aggregate potential to emit of less than 100 tons per year of CO shall no longer apply if the District is redesignated by the federal Environmental Protection Agency (EPA) as in attainment with respect to the national ambient air quality standard for CO.
  4. "Type II Portable Emission Unit" means a portable emission unit that can be operated only at stationary sources which have an aggregate potential to emit of less than the emission rates listed in Table 20.4 - 1. Type II portable emission units may also operate at stationary sources which have an aggregate potential to emit greater than the emission rates listed in Table 20.4 - 1, if emission offsets at the ratios specified for Type III portable emission units are provided for the period of time the portable emission unit is located at such a stationary source. The limitation on operating at stationary sources which have an aggregate potential to emit of less than 100 tons per year of CO shall no longer apply if the District is redesignated by the federal EPA as in attainment with respect to the national ambient air quality standard for CO.
 
TABLE 20.4 - 1 
Federal Serious Ozone Nonattainment Cassification
Air Contaminant: Emission Rate  
(Ton/yr)
Oxides of Nitrogen (Nox)  

Volatile Organic Compounds (VOC)  

Carbon Monoxide (CO)

50  

50  

100

 
 
  1.  "Type III Portable Emission Unit" means a portable emission unit that can be operated at any stationary source, regardless of the source's aggregate potential to emit.
(d) STANDARDS
 
  1.  BACT and LAER for New or Modified Portable Emission Units

  2. The Air Pollution Control Officer shall deny an Authority to Construct or modified Permit to Operate for any new or modified portable emission unit unless the applicant demonstrates that the following requirements will be satisfied:
    (iii)    New or Modified Portable Emission Units - PSD Stationary Sources
    Any new or modified portable emission unit which may be located at a Prevention of Significant Deterioration (PSD) stationary source, which emission unit has an emission increase of one or more air contaminants which constitutes a new PSD stationary source (see Table 20.1-11) or PSD modification (see Tables 20.1-8 and 20.1-10) shall be equipped with BACT for each such air contaminant.
     
  1.  Air Quality Impact Analysis (AQIA)
  2. The Air Pollution Control Officer shall deny an Authority to Construct or modified Permit to Operate for any portable emission unit unless the following requirements are satisfied. Modeling shall be used to conduct any Air Quality Impact Analysis (AQIA). The AQIA shall be performed using maximum expected ambient air contaminant concentrations within San Diego County, based on existing data, unless the applicant agrees to enforceable permit conditions that requires a new AQIA whenever the equipment is to be located at a stationary source for which the initial AQIA was not representative. Area fugitive emissions of PM10 shall not be included in the demonstrations required below, unless the Air Pollution Control Officer determines, on a case-by-case basis, that a project's area fugitive emissions of PM10 must be evaluated in order to protect public health and welfare.
 
TABLE 20.4 - 2 
AQIA Trigger Levels
Emission Rate
Air Contaminant (lb/hr) (lb/day) (tons/yr)
Particulate Matter (PM10 

Oxides of Nitrogen (Nox)  

Oxides of Sulfur (Sox)  

Carbon Monoxide (CO)  

Lead and Lead Compounds

--- 

25  

25  

100 

---

100  

250  

250  

550  

3.2

15  

40  

40  

100  

0.6

   
  1. Prevention of Significant Deterioration (PSD)

  2. The Air Pollution Control Officer shall deny an Authority to Construct or modified Permit to Operate for any portable emission unit which is expected to have a significant impact on any Class I area, as determined by an AQIA required pursuant to Subsection (d)(2), unless the following requirements are satisfied.
 
  1. Public Notice and Comment

  2. The Air Pollution Control Officer shall not issue an Authority to Construct or modified Permit to Operate for any portable emission unit subject to the AQIA or notification requirements of Subsections (d)(2) or (d)(3), nor for any project which results in an emissions increase of VOCs equal to or greater than 250 pounds per day or 40 tons per year, unless the following requirements are satisfied.
 
  1. Emission Offsets
 
 
TABLE 20.4 - 3 
Interpollutant Ratio
Emission Increase Decrease Interpollutant Ratio
Oxides of Nitrogen (NOx) NOx  
VOC
1.0  
2.0
Volatile Organic Compounds (VOC) VOC  
NOx
1.0  
1.0