(a) Not later than October 1, 1975, the Commonwealth shall have developed and have begun to implement a program to identify urban and suburban core areas and roadway/intersection complexes within the Boston Intrastate Region which violate the national ambient air quality standards for carbon monoxide. Once such localized areas have been identified, the Commonwealth, in cooperation with the affected local municipalities, shall develop and implement appropriate control strategies to insure that such air quality standards will be achieved at such areas. Plans shall be developed to include provisions for the entire municipality in order to insure that the implemented strategies will not create carbon monoxide violations elsewhere in the vicinity after the measures have been applied.

(b) To accomplish the requirements of paragraph (a) of this section, the Commonwealth shall do the following:

(1) Identify areas of potentially high carbon monoxide concentrations by reviewing all available traffic data, physical site data and air quality and meteorological data for all major intersections and roadway complexes within the Region. The Regional Administrator will provide general guidance on area designations to assist in the initial identification process.

(2) Areas identified under paragraph (b)(1) of this section shall be studied in further detail, including meteorological modeling, traffic flow monitoring, air quality monitoring and other measures necessary to accurately quantify the extent and actual levels of carbon monoxide in the area. A report containing the results of these analyses and identifying such areas shall be submitted to the Regional Administrator no later than March 1, 1976.

(3) If, after the completion of actions required by paragraph (b)(2) of this section, an area shows or is predicted to have violations of the carbon monoxide standard, the Commonwealth, in cooperation with the affected municipality, shall submit a plan to the Regional Administrator containing measures to regulate traffic and parking so as to reduce carbon monoxide emissions to achieve air quality standards in the area. Such plan shall include: the name of the agency responsible for implementing the plan, all technical data and analyses supporting the conclusions of the plan, all control strategies adopted as part of the plan, and other such information relating to the proposed program as may be required by the Regional Administrator. The Regional Administrator shall provide general guidance on applicable control strategies and reporting formats to assist in plan development and submittal. Such a plan shall be submitted for each municipality which contains one or more identified areas no later than October 1, 1975 for Waltham and October 1, 1976, for other areas.

(4) All measures called for in the plan submitted under paragraph (b)(3) of this section shall be subject to the approval of the Regional Administrator and shall be implemented by May 31, 1977.

(c) The Commonwealth shall annually review the effectiveness of the control strategies developed pursuant to this section and modify them as necessary to insure that such carbon monoxide standards will be attained and maintained. The results of this review and any changes in the measures which the Commonwealth recommends as a result thereof shall be reported to the Regional Administrator annually as required under § 52.1160.

(d) Prior to submitting any plan to the Regional Administrator under paragraph (b)(3), the Commonwealth shall give prominent public notice of the general recommendations of such plan, shall make such plan available to the public for at least 30 days and permit any affected public agency or member of the public to comment in writing on such plan. The Commonwealth shall give the Regional Administrator timely notice of any public hearing to be held on such plan and shall make all comments received available to the Regional Administrator for inspection and copying.