available if based on use of the measurement methods specified in § 51.17; sulfur dioxide measurements based on use of the continuous conductimetric method also will be acceptable for this purpose. If actual measurements are not available and cannot be made in time to be employed in the development of the control strategy, air quality may be estimated by the procedure described in Appendix A to this part. Air quality data, whether measured or estimated, shall be submitted in a form similar to that shown in Appendix H to this part.

§ 51.14 Control strategy: Carbon monoxide, hydrocarbons, photochemical oxidants, and nitrogen dioxide.

(a) Priority I Regions. (1) Each plan for a region classified Priority I with respect to carbon monoxide, photochemical oxidants, or nitrogen dioxide shall set forth a control strategy which shall provide for the degree of emission reduction necessary for attainment and maintenance of the national standard for each such pollutant after consideration of the emission reductions that will result from the application of Federal motor vehicle emission standards promulgated pursuant to section 202 of the Act.

(2) The plan shall contain:
(i) A

description of enforcement methods including, but not limited to, procedures for monitoring compliance with the selected traffic control measures, procedures for handling violations, and a designation of enforcement responsibilities (i.e., air pollution control agency, State police, State Department of Motor Vehicles, State Registrar of Motor Vehicles, etc.).

(ii) Proposed or adopted rules and regulations pertaining to the selected transportation control measures.

(iii) A description of administrative procedures to be used in implementing all selected transportation control measures, including, but not limited to, methods of achieving transportation improvements and a designation of responsibility for administration of such procedures (e.g., State Treasurer responsible for purchase of buses).

(iv) A schedule designating dates by which legal authority necessary to implement the plan will be obtained, other significant steps in the implementation of the plan will be achieved, and each control measure will be implemented.

(b) Control strategy development. In a region in which attainment and maintenance of a national standard will require emission reductions in addition to those which will result from application of the Federal motor vehicle emission standards, the control strategy shall provide for application of such other measures as may be necessary for attainment and maintenance of such national standard.

(c) Adequacy of control strategy (1). The plan shall demonstrate, by means of a proportional model or diffusion/photochemical model or other procedure which is adequate and appropriate, that the control strategy included in each plan for a region classified as priority I is adequate for attainment and maintenance of the national standard(s) to which such control strategy applies. Control measures shall not result in an increase in the concentration of any pollutant to a level that exceeds a national ambient air quality standard. The plan shall include provisions as necessary to prevent such increases in concentrations as a result of traffic increases that may be stimulated by transportation control

measures.

(2) With respect to control of carbon monoxide and nitrogen oxides, the proportional model which may be used for purposes of this paragraph is described in § 51.13(e) (2): Provided, With respect to the national standard for nitrogen dioxide, that the degree of air quality improvement indicated to be necessary by the proportional model will be achieved by a corresponding degree of reduction of total nitrogen oxides emissions from stationary and mobile sources.

(3) In any region where the degree of nitrogen oxides emission reduction necessary for attainment and maintenance of the national standard for nitrogen dioxide is greater than that which can be achieved by the application of (i) the Federal motor vehicle emission standards promulgated under section 202 of the Act and (ii) any transportation control measures which may be necessary for attainment and maintenance of the national standards for carbon monoxide and photochemical oxidants, the plan shall provide for the degree of nitrogen oxides emission reduction attainable through the application of reasonably available control technology.

(4) With respect to hydrocarbons and photochemical oxidants, it may be assumed that (i) there is no background concentration of photochemical oxidants and (ii) the degree of total hydrocarbon emission reduction necessary for attainment and maintenance of the national standard for photochemical oxidants will also be adequate for attainment of the national standard for hydrocarbons. The proportional model to be used to determine the necessary hydrocarbon emission reduction is set forth in Appendix J to this part.

(5) The plan shall show that the control strategy including transportation control measures will result in the degree of emissions reduction indicated to be necessary by a proportional model, diffusion model, or other procedure which is adequate and appropriate. The plan shall contain a summary of the computations, assumptions and judgments used to determine the emissions reductions that will result from application of the control strategy to each point source, and each group of area sources. Such summary shall be included in a table similar to that presented in appendix D to this part. The plan also shall contain a sum

Pollutants

mary of the data, computations, assumptions and judgments used to develop any transportation control measures that are a part of the control strategy. Such a summary shall as a minimum contain the material described in appendix M to this part. The detailed computations and data shall be retained by the State and made available for inspection by the Administrator at his request.

(6) If a diffusion/photochemical model is used, the plan shall include a description of such model.

(d) Emission data. Emission data on carbon monoxide, hydrocarbons, and nitrogen oxides shall be submitted in accordance with the requirements of

§ 51.13 (f).

(e) Air quality data. Data showing existing air quality levels shall be presented in accordance with this section:

(1) For Priority I regions, data on carbon monoxide, nitrogen dioxide, and photochemical oxidants shall, as a minimum, include the results of measurements made during a period of approximately 3 months beginning on or about July 1, 1971, in accordance with the following procedures.

1 Equivalent methods are specified in § 420.17. (2) For Priority I regions, only available air quality data for hydrocarbons must be submitted.

(3) For Priority III regions, no air quality data for carbon monoxide, hydrocarbons, nitrogen dioxide, and photochemical oxidants need be submitted.

(4) Air quality data required by this subparagraph shall be submitted in the form similar to that shown in Appendix H to this part.

(f) Motor vehicle emission factors.The States required to submit transportation control plans must, except as noted below, use current emission factors and methodology to calculate emissions from gasoline powered motor vehicles. The current emission factors and methodology are presented in "Compila

tion of Air Pollutant Emission Factors," EPA Report No. AP-42, and in superseding EPA interim reports. These are available from the EPA, Office of Air Quality Planning and Standards, Research Triangle Park, N.C. 27711. If emissions factors or methodology other than those presented in the EPA report are used, the substantiating justification must be submitted with the transportation control

measures.

(g) Air quality base line.-The concentrations of carbon monoxide and photochemical oxidants set forth in the State plan as approved and promulgated on May 31, 1972 (37 FR 10842), (part 52 of this chapter), may be used as the air quality base lines for computation of the emissions reductions through transporta

tion control measures required to meet national standards. More recent air quality data should be used where adequate and appropriate. Such data must be compatible with the emissions inventory for the region involved and justification submitted for the appropriateness of its use. Revised air quality data should be submitted to the appropriate EPA regional office at the earliest possible date for evaluation and approval to preclude plan disapproval resulting from the use of faulty air quality data.

(h) Transportation control strategies.-Information and requirements for States which are considering transportation control measures involving inspection, maintenance, and retrofit of in-use motor vehicles are presented in appendix N to this part.

[36 FR 22398, Nov. 15, 1971, as amended at 36 FR 25233, Dec. 30, 1971; 38 FR 15195, June 8, 1973]

§ 51.15 Compliance schedules.

(a) (1) Each plan shall contain legally enforceable compliance schedules setting forth the dates by which all stationary and mobile sources or categories of such sources must be in compliance with any applicable requirement of the plan. Such compliance schedules shall contain increments of progress required by paragraph (c) of this section.

(2) A plan may provide that compliance schedules for individual sources or categories of sources will be formulated following submittal of the plan. Such compliance schedules shall be submitted to the Administrator within 60 days following the date such schedule is adopted but in no case later than the prescribed date for submittal of the first semiannual report required by § 51.7: Provided, however, That compliance schedules for nitrogen oxides required for stationary source shall be submitted to the Administrator no later than the prescribed date for the submittal of the second semiannual report required by § 51.7. Where submission of compliance schedules is deferred by a State under this subparagraph, the plan shall specify a final compliance date applicable to each source subject to an applicable requirement of the plan. Compliance schedules submitted pursuant to this subparagraph shall require each source or category of sources to comply with such requirement

within the times specified in paragraph (b) of this section but in no event later than the date specified in the plan for final compliance with such requirement.

(b) (1) Any compliance schedule designed to provide for attainment of a primary standard shall provide for compliance with the applicable plan requirements as expeditiously as practicable and in no case, except as provided by Subpart C of this part, later than the date specified for attainment of such primary standard pursuant to § 51.10(b).

(2) Any compliance schedule designed to provide for attainment of a secondary standard shall provide for compliance with the applicable plan requirements in a reasonable time and in no case, except as provided by Subpart C of this part, later than the date specified for the attainment of such secondary standard pursuant to § 51.10(c).

(c) Any compliance schedule or revision thereof extending over a period of more than 1 year from the date of its adoption by the State agency shall provide for legally enforceable increments of progress toward compliance by each affected source or category of sources: Provided however: That increments of progress shall not be required for a compliance schedule which does not extend beyond January 31, 1974. Increments of progress shall include, where practicable, each increment of progress specified in § 51.1 (q) and shall include such additional increments of progress as may be necessary to permit close and effective supervision of progress toward timely compliance.

[37 FR 26312, Dec. 9, 1972]

§ 51.16 Prevention of air pollution emergency episodes.

(a) For the purpose of preventing air pollution emergency episodes, each plan for a Priority 1 region shall include a contingency plan which shall, as a minimum, provide for taking any emission control actions necessary to prevent ambient pollutant concentrations at any location in such region from reaching levels which could cause significant harm to the health of persons, which levels are as follows:

Sulfur dioxide-2,620 micrograms/cubic meter (1.0 part per million), 24-hour average. Particulate matter-1,000 micrograms/cubic meter or 8 COH's, 24-hour average.

Sulfur dioxide and particulate matter combined-product of sulfur dioxide in micrograms/cubic meter, 24-hour average, and particulate matter in micrograms/cubic meter, 24-hour average, equal to 490 X 103 or product of sulfur dioxide in parts per million, 24-hour average and COH's, 24hour average, equal to 1.5. Carbon monoxide:

57.5 milligrams/cubic meter (50 parts per million), 8-hour average.

86.3 milligrams/cubic meter (75 parts per million), 4-hour average.

144 milligrams/cubic meter (125 parts per million), 1-hour average. Photochemical oxidants:

800 micrograms/cubic meter (0.4 part per million), 4-hour average.

1,200 micrograms/cubic meter (0.6 part per million), 2-hour average.

1,400 micrograms/cubic meter (0.7 part per million), 1-hour average.

Nitrogen dioxide:

3,750 micrograms/cubic meter (2.0 parts per million), 1-hour average.

938 micrograms/cubic meter (0.5 part per million), 24-hour average.

(b) Each contingency plan shall (1) specify two or more stages of episode criteria such as those set forth in Appendix L to this part, or their equivalent (2) provide for public announcement whenever any episode stage has been determined to exist, and (3) specify emission control actions to be taken at each episode stage, including, but not necessarily limited to, actions such as those set forth in Appendix L to this part, or their equivalent.

(c) (1) For each stationary source emitting 100 tons (90.7 metric tons) per year or more, the contingency plan shall include, or provide for preparation of, a specific legally enforceable emission control action program and shall show that the owner and/or operator of such stationary source has been notified of the requirements of such emission control action program.

(2) Any emission control action programs required by subparagraph (1) of this paragraph which are not included in the contingency plan shall be submitted to the Administrator in the first semiannual report required under § 51.7. Unless disapproved by the Administrator, such emission control action programs shall be part of the applicable plan.

(d) To the maximum extent practicable, emission control actions taken

pursuant to a contingency plan shall be consistent with the extent of any air pollution episode, e.g., if a single source is determined to be responsible for the occurrence of any episode stage, then the emission control action steps applicable to such source shall be taken.

(e) Each contingency plan for a Priority I region shall provide for:

(1) Daily acquisition of forecasts of atmospheric stagnation conditions or during any episode stage and updating of such forecasts at least every 12 hours.

(2) Inspection of sources to ascertain compliance with applicable emission control action requirements.

(3) Communications procedures for transmitting status reports and orders as to emission control actions to be taken during an episode stage, including procedures for contact with public officials, major emission sources, public health, safety, and emergency agencies and news media.

(f) In the event that the requirements of paragraphs (c) and (e) of this section have not been fully met by the prescribed date for submitting a plan, a description of the steps under consideration and a timetable for their completion shall be submitted with the plan. Such timetable shall provide for meeting all requirements of paragraphs (c) and (e) of this section within 1 year after such prescribed date. A description of interim actions that will be taken to control emissions during any episode stage which occurs during such 1-year period shall be included.

(g) Each plan for a Priority II region shall include a contingency plan meeting, as a minmum, the requirements of subparagraphs (1) and (2) or paragraph (b) of this section.

[36 F.R. 22398, Nov. 25, 1971; 36 F.R. 24002, Dec. 17, 1971]

Tape sampler.

One sample every 2 hours..

Pararosaniline or equivalent d. One 24-hour sample every 6 days (gas bubbler).

Photochemical oxidants... Gas phase chemiluminesence

or equivalent.

24-hour sampling method (Jacobs-Hochheiser

method).

High volume sampler.. Tape sampler.

One 24-hour sample every 14 days (gas bubbler).b

One 24-hour sample every 6 days One sample every 2 hours..

Pararosaniline or equivalent d. One 24-hour sample every 6 days

(gas bubbler).

Continuous.

Equivalent to 61 random samples per year.

b Equivalent to 26 random samples per year.

Less than 100,000... 100,000-1,000,000... 1,000,001-5,000,000.. Above 5,000,000.. Less than 100,000. 100,000-5,000,000... Above 5,000,000.Less than 100,000.. 100,000-5,000,000.. Above 5,000,000... Less than 100,000.. 100,000-5,000,000.. Above 5,000,000... Less than 100,000. 100,000-1,000,000.. Above 1,000,000..

3.

2.5+0.5 per 100,000 population. 6+0.15 per 100,000 population. 11+0.05 per 100,000 population.

d Equivalent methods are (1) Gas Chromatographic Separation-Flame Photometric Detection (provided Teflon is used throughout the instrument system in parts exposed
to the air stream), (2) Flame Photometric Detection (provided interfering sulfur compounds present in significant quantities are removed), (3) Coulometric Detection (provided
oxidizing and reducing interferences such as O3. NO2, and H2S are removed), and (4) the automated Pararosaniline Procedure.
Equivalent method is Gas Chromatographic Separation-Catalytic Conversion-Flame Ionization Detection.

Equivalent methods are (1) Potassium Iodide Colorimetric Detection (provided a correction is made for SO; and NO2), (2) UV Photometric Detection of Ozone
(provided compensation is made for interfering substances), and (3) Chemiluminesence Methods differing from that of the reference method.
It is assumed that the Federal motor vehicle emission standards will achieve and maintain the national standards for carbon monoxide, nitrogen dioxide, and
photochemical oxidants; therefore, no monitoring sites are required for these pollutants.

h In interstate regions, the number of sites required should be prorated to each State on a population basis.

All named measurement methods, except the Tape Sampler method, are described in the national ambient air quality standards published April 30, 1971 (36 F.K. 8186). Other methods, including, but not necessarily limited to, those specified under footnotes (d), (e), and (D), will be considered equivalent if they meet the definition of "Equivalent Method" set forth in such national ambient air quality standards and if they meet the following performance specifications: