(ii) The more restrictive classification will be chosen where there is a difference between the maximum value(s) and the annual averages e.g., if a region is Priority I with respect to an annual average and Priority II with respect to a 24-hour maximum value, the classification will be Priority I.

(2) Procedures which may be used, where appropriate, to estimate air quality in regions where no measured data or inadequate data exist are described in Appendix A to this part.

(b) For carbon monoxide, nitrogen dioxide, and photochemical oxidants, each region will be classified into one of two categories defined as Priority I or Priority III.

(1) Ambient concentration limits which define the classification system

are:

(i) Carbon monoxide: Priority I: Equal to or above 55 milligrams per cubic meter (48 p.p.m.), 1-hour maximum, or 14 milligrams per cubic meter (12 p.p.m.), 8-hour maximum; Priority III: Below such values.

(ii) Nitrogen dioxide: Priority I: Equal to or above 110 micrograms per cubic meter (0.06 p.p.m.) annual arithmetic mean; Priority III: Below such value.

(iii) Photochemical oxidants: Priority I: Equal to or above 195 micrograms per cubic meter (0.10 p.p.m.), 1hour maximum; Priority III: Below such value.

(2) In the absence of measured data to the contrary, classification with respect to carbon monoxide, photochemical oxidants and nitrogen dioxide will be based on the following estimate of the relationship between these pollutants and population: Any region containing an area whose 1970 "urban place" population, as defined in the U.S. Bureau of Census, exceeds 200,000 will be classified Priority I. All other regions will be classified Priority III.

(3) Where a region is classified Priority I on the basis of population, the air quality data requirements of § 51.14 (e) (1) shall apply. If these data indicate the pollutant concentrations are below the values stipulated in subparagraph (1) of this paragraph, the region will be reclassified Priority III.

(4) Classifications with respect to hydrocarbons will be the same as the classifications with respect to photochemical oxidants.

(c) Where a region is classified Priority I on the basis of measured or estimated air quality levels reflecting emissions predominantly from a single point source, it shall be further classified Priority IA. The requirements applicable to Priority IA regions shall be the same as those for other Priority I regions, except that the requirements applicable to Priority II regions under §§ 51.16 and 51.17 shall apply. A procedure for estimating air quality levels reflecting emissions from a single point source is described in Appendix A to this part.

§ 51.4 Public hearings.

(a) (1) Except as otherwise provided in subparagraph (2) of this paragraph, the State shall, prior to the adoption of any plan or any revision thereof required by 51.6(a) or prior to the submission to the Administrator of any individual compliance schedule pursuant to § 51.15 (a) or any revision pursuant to § 51.6(d), conduct one or more public hearings on such plan, schedule, or revision. Separate hearings may be held for plans to implement primary and secondary standards.

(2) No hearing shall be required for any change to an increment of progress in an approved individual compliance schedule unless such change is likely to cause the source to be unable to comply with the final compliance date in the schedule. The requirements of §§ 51.6 and 51.8 shall be applicable to such schedules, however.

(b) Any hearing required by paragraph (a) of this section shall be held only after reasonable notice, which shall be considered to include, at least 30 days prior to the date of such hearing(s):

(1) Notice given to the public by prominent advertisement in the region affected announcing the date(s), time(s), and place(s) of such hearing(s);

(2) Availability of each proposed plan or revision for public inspection in at least one location in each region to which it will apply, and the availability of each compliance schedule for public inspection in at least one location in the region in which the affected source is located;

(3) Notification to the Administrator (through the appropriate Regional Office);

(4) Notification to each local air pollution control agency in each region to which the plan, schedule, or revision will apply; and

(5) In the case of an interstate region, notification to any other States included, in whole or in part, in the region.

(c) The State shall prepare and retain, for inspection by the Administrator upon his request, a record of each hearing. The record shall contain, as a minimum, a list of witnesses together with the text of each presentation.

(d) The State shall submit with the plan, revision, or schedule a certification that the hearing required by paragraph (a) of this section was held in accordance with the notice required by paragraph (b) of this section.

(e) Upon written application by a State agency (through the appropriate Regional Office), the Administrator may approve State procedures designed to insure public participation in the matters for which hearings are required, and public notification of the opportunity to participate if in the judgment of the Administrator, such procedures, although different from the requirements of this part, in fact provide for adequate notice to and participation of the public. The Administrator may impose any conditions on his approval as he deems necessary. Procedures approved pursuant to this section shall be deemed to satisfy the requirements of this part regarding public hearings.

(f) The State shall, prior to adoption of transportation control measures, conduct one or more public hearings as required in paragraphs (a) through (d) of this section.

[37 FR 26311, Dec. 9, 1972, as amended at 38 FR 15195, June 8, 1973]

§ 51.5 Submission of plans; preliminary review of plans.

(a) Submission to the Administrator shall be accomplished by delivering five copies of the plan to the appropriate Regional Office and a letter to the Administrator notifying him of such action. Plans shall be adopted by the State and submitted to the Administrator by the Governor as follows:

(1) For any primary standard, within 9 months after promulgation of such standard.

NOTE: The State of Illinois shall, not later than September 9, 1974, submit to the Administrator a demonstration that the control strategy approved by the Administrator for the Metropolitan Chicago Air Quality Control Region is adequate to attain and maintain the national standard for nitrogen dioxide.

(2) For any secondary standard, within 9 months after promulgation of such secondary standard or by such later date prescribed by the Administrator pursuant to Subpart C of this part.

(3) For compliance with the requirements of §§ 51.11(a) (4) and 51.18, no later than August 15, 1973.

(b) Plans for different regions within a State may be submitted as a single document or as separate documents.

(c) Upon request of a State, the Administrator will provide preliminary review of a plan or portion thereof submitted in advance of the date such plan is due. Such requests shall be made in writing to the appropriate Regional Office and shall be accompanied by five copies of the materials to be reviewed. Requests for preliminary review shall not operate to relieve a State of the responsibility of adopting and submitting plans in accordance with prescribed due dates.

(d) Submission to the Administrator shall be accomplished by delivering 10 copies of the transportation control portions of the plan to the appropriate regional office. Such portions shall be adopted by the State and submitted by the Governor.

(e) Upon request of a State, the Administrator will provide preliminary review of the draft transportation control measures or portions thereof in advance of the date such measures are due. Such requests shall be made as provided in paragraph (c) of this section and shall not operate to relieve a State of its responsibility for adopting and submitting transportation control measures in accordance with prescribed due dates. [36 FR 22398, as amended at 38 FR 15195. June 8, 1973, 38 FR 15836, June 18, 1973; 39 FR 16122, May 7, 1974]

51.6 Revisions.

(a) The pian shall be revised from time to time, as may be necessary, to take account of:

(1) Revisions of national standards,

(2) The availability of improved or more expeditious methods of attaining such standards, such as improved technology or emission charges or taxes, or

(3) A finding by the Administrator that the plan is substantially inadequate to attain or maintain the national standard which it implements.

(b) The plan shall be revised within 60 days following notification by the Administrator under paragraph (a) of this section, or by such later date prescribed

by the Administrator after consultation with the State.

(c) The plan may be revised from time to time consistent with the requirements applicable to implementation plans under this part.

(d) Any revision of any regulation or any compliance schedule pursuant to paragraph (c) of this section shall be submitted to the Administrator no later than 60 days after its adoption.

by paragraphs (a) and (d) of this section shall be identified and described in the next semiannual report required by § 51.7.

(f) Any revision shall be submitted only after any applicable hearing requirements of § 51.4 have been satisfied. [37 FR 22398, Nov. 25, 1971, as amended at 37 FR 26312, Dec. 9, 1972]

(a) Quarterly report on air quality data. On a quarterly basis commencing with the end of the first quarterly period of October 1-December 31, 1972, the State agency shall report to the Administrator (through the appropriate Regional Office) information on air quality as specified in this paragraph.

(1) Quarterly reports shall include all air quality data gathered during the reporting period by the air quality surveillance network which is part of the applicable plan. The first report shall include all air quality data gathered subsequent to the air quality data which provided the basis for the development of the applicable plan.

(2) Quarterly reports shall be recorded and submitted in accordance with the procedures and data forms specified in the Storage and Retrieval of Aerometric Data (SAROAD) Users Manual, USEPA, OAP, APTD-0663. The data shall be submitted on paper forms, punched cards, or magnetic tape in the SAROAD format as specified in the following forms:

(i) SAROAD Site Identification Form for each new sampling site.

(ii) SAROAD Hourly Data Form for data with a sampling interval of less than 24 hours.

(iii) SAROAD Daily Data Form for data with a sampling interval of 24 hours or greater.

each reporting period. The quarterly periods are January 1-March 31, April 1June 30, July 1-September 30 and October 1-December 31.

(b) Semiannual report. (1) For purposes of paragraph (a)(3) and paragraph (4) (i) and (ii) of this section, the term source shall have the following meaning: Any facility which emits a total of more than 100 tons per year of any one pollutant for which a national standard has been promulgated. For such facilities, emissions shall be reported as follows:

(i) Emissions of each such pollutant for the facility as a whole.

(ii) Emissions of each such pollutant from any individual emission point within the facility which emits more than 25 tons per year of any such pollutant.

(2) Submission of report: On a semiannual basis commencing with the end of the first semiannual period of July 1December 31, 1972, the State agency shall report to the Administrator (through the appropriate Regional Office) information as specified in this section.

(3) Source inventory data: (i) Emissions data and information related to emissions as identified by the NEDS point source coding forms shall be reported for each source which achieved compliance at any time within the reporting period with any regulation of an applicable plan. The first report shall include all sources which achieved compliance since the development of the applicable plan.

(ii) Emissions data and information related to emissions for criteria pollutants shall be reported for each new or modified source which:

(a) Received approval to construct during the reporting period.

(b) Began operation during the reporting period. The first report shall include all new or modified sources which began operation since the development of the applicable plan.

(iii) The identification of sources which ceased operations during the reporting period shall be reported. The first report shall identify all sources which ceased operation since the development of the applicable plan.

(iv) The data required by paragraphs (b) (3) (i), (ii) and (iii) of this section shall be recorded and submitted on the NEDS point source coding forms specified in the "Guide for Compiling a Comprehensive Emission Inventory," Revised (March 1973), USEPA, OAWP, ATPD1135.

(4) Progress in plan enforcement: (i) For each source, achievement during the reporting period of any increment of progress of compliance schedules required by the applicable plan or by any enforcement order or other State action required to be submitted pursuant to paragraph (d) shall be reported.

(ii) For each source, any enforcement action taken during the reporting period and not submitted under paragraph (d) which results in civil or criminal penalties shall be reported.

(iii) For each category of area sources, an estimate of the percent of sources in compliance with any emission regulation of the applicable plan shall be reported.

(5) Revisions: All substantive revisions, during the reporting period of the applicable plan, other than revisions to rules and regulations or compliance schedules submitted in accordance with section 51.6(g) of this part shall be identified and described. Substantive revisions shall include but are not limited to changes in stack-test procedures for determining compliance with applicable regulations, modifications, in the projected total manpower needs to carry out the approved plan, all changes in responsibilities given to local agencies to carry out various portions of the plan.

(6) Submission of semi-annual report: Semi-annual reports shall be submitted within 45 days after the end of each reporting period. The semi-annual periods are January 1-June 30 and July 1-December 31.

(c) Report format. Where a State agency has an existing format for recording the information required by paragraphs (a) and (b) of this section that differs from the format specified in those paragraphs, the State agency must obtain approval of the format by the Administrator (through the appropriate Regional Office) prior to its submittal as part of the quarterly or semiannual report.

(d) Report on enforcement orders and other state actions. (1) Any enforcement orders, including any court order, and any state action which purports to modify the requirements of an applicable implementation plan shall be submitted to the Administrator within 60 days of its issuance or adoption by the State.

(2) A State enforcement order or other State action shall not revise the applicable implementation plan unless such order or action is submitted as a revision

to such plan pursuant to § 51.6 and approved by the Administrator.

[38 FR 20834, Aug. 3, 1973]

§ 51.8 Approval of plans.

The Administrator shall approve any plan, or portion thereof, or any revision of such plan, or portion thereof, if he determines that it meets the requirements of the Act. Revisions of a plan, or any portion thereof, shall not be considered part of an applicable plan until such revisions have been approved by the Administrator in accordance with this part.

Subpart B-Plan Content and
Requirements

§ 51.10

General requirements.

(a) During development of a plan, the State is encouraged to identify alternative control strategies, as well as the costs and benefits of each such alternative, for attainment and maintenance of the national standards.

(b) Each plan implementing a primary standard shall provide for the attainment of such standard as expeditiously as practicable, but in no case, except as otherwise provided by Subpart C of this part, later than 3 years after the date of the Administrator's approval of such plan or any revision thereof to take account of a revised primary standard. The projected date of attainment of such standard shall be specified in the plan.

(c) Each plan implementing a secondary standard shall provide for the attainment of such standard by a specified date, which shall be within a reasonable time after the date of the Administrator's approval of such plan.

(d) The plan for each region shall have adequate provisions to insure that pollutant emissions within such region will not interfere with attainment and maintenance of any national standard in any portion of an interstate region or in any other region.

(e) Each plan shall provide for public availability of emission data reported by source owners or operators or otherwise obtained by a State or local agency. Such emission data shall be correlated with applicable emission limitations or other measures. As used in this paragraph, "correlated" means presented in such a manner as to show the relationship between measured or estimated amounts of emissions and the amounts

of such emissions allowable under the applicable emission limitations or other

measures.

§ 51.11 Legal authority.

(a) Each plan shall show that the State has legal authority to carry out the plan, including authority to:

(1) Adopt emission standards and limitations and any other measures necessary for attainment and maintenance of national standards.

(2) Enforce applicable laws, regulations, and standards, and seek injunctive relief.

(3) Abate pollutant emissions on an emergency basis to prevent substantial endangerment to the health of persons, i.e., authority comparable to that available to the Administrator under section 303 of the Act.

(4) Prevent construction, modification, or operation of a facility, building, structure, or installation, or combination thereof, which directly or indirectly results or may result in emissions of any air pollutant at any location which will prevent the attainment or maintenance of a national standard.

(5) Obtain information necessary to determine whether air pollution sources are in compliance with applicable laws, regulations, and standards, including authority to require recordkeeping and to make inspections and conduct tests of air pollution sources.

(6) Require owners or operators of stationary sources to install, maintain, and use emission monitoring devices and to make periodic reports to the State on the nature and amounts of emissions from such stationary sources; also authority for the State to make such data available to the public as reported and as correlated with any applicable emission standards or limitations.

(b) Where a plan sets forth a control strategy that provides for application of (1) inspection and testing of motor vehicles and/or other transportation control measures or (2) land use measures other than those referred to in § 51.11(a)(4), such plan shall set forth the State's timetable for obtaining such legal authority as may be necessary to carry out such measures.

(c) The provisions of law or regulation which the State determines provide the authorities required under this section shall be specifically identified, and copies of such laws or regulations shall be submitted with the plan.

(d) (1) Except as otherwise provided by paragraph (b) of this section, the plan shall show that the legal authorities specified in this section are available to the State at the time of submission of the plan.

(2) Legal authority adequate to fulfill the requirements of paragraph (a) (5) and (6) of this section may be delegated the State pursuant to section 114 of the Act.

(e) A State governmental agency other than the State air pollution control agency may be assigned responsibility for carrying out a portion of a plan: Provided, That such plan demonstrates, to the Administrator's satisfaction, that such State governmental agency has the legal authority necessary to carry out such portion of the plan or, pursuant to paragraph (b) of this section, has a timetable for obtaining such authority.

(f) The State may authorize a local agency to carry out a plan, or portion thereof, within such local agency's jurisdiction: Provided, That such plan demonstrates, to the Administrator's satisfaction, that such local agency has the legal authority necessary to implement such plan, or portion thereof, and further: Provided, That such authorization shall not relieve the State of responsibility under the Act for carrying out such plan, or portion thereof.

[36 FR 22398, as amended at 38 FR 15836, June 18, 1973]

§ 51.12 Control strategy: General.

(a) In any region where existing (measured or estimated) ambient levels of a pollutant exceed the levels specified by an applicable national standard, the plan shall set forth a control strategy which shall provide for the degree of emission reduction necessary for attainment and maintenance of such national standard, including the degree of emission reduction necessary to offset emission increases that can reasonably be expected to result from projected growth of population, industrial activity, motor vehicle traffic, or other factors that may cause or contribute to increase emissions.

(b) In any region where measured or estimated ambient levels of a pollutant are below the levels specified by an applicable secondary standard, the plan shall set forth a control strategy which shall be adequate to prevent such ambient pollution levels from exceeding such secondary standard.