(a) For purposes of this subpart, the definitions herein are applicable.

(b) Definitions:

(1) Register as applied to a motor vehicle, means the licensing of such motor vehicle for general operation on public roads or highways by the appropriate agency of the Federal Government or by the Commonwealth.

(2) Boston Intrastate Region means the Metropolitan Boston Intrastate Air Quality Control Region, as defined in § 81.19 of this part.

(3) [Reserved]

(4) Freeze area means that portion of the Boston Intrastate Region enclosed within the following boundaries:

The City of Cambridge; that portion of the City of Boston from the Charles River and the Boston Inner Harbor on north and northeast of pier 4 on Northern Avenue; by the east side of pier 4 to B Street, B Street extension of B Street to B Street, B Street, Dorchester Avenue, and the Preble Street to Old Colony Avenue, then east to the water, then by the water's edge around Columbia Point on various courses generally easterly, southerly, and westerly to the center of the bridge on Morrissey Boulevard, on the east and southeast; then due west to Freeport Street, Freeport Street, Dorchester Avenue, Southeast Expressway, Southampton Street, Reading Street, Island Street, Chadwick Street, Carlow Street, Albany Street, Hunneman Street, Madison Street, Windsor Street, Cabot Street, Ruggles Street, Parker Street, Ward Street, Huntington Avenue, Brookline-Boston municipal boundary, Mountford Street to the Boston University Bridge on the southwest and west; and the Logan International Airport. Where a street or roadway forms a boundary the entire right-of-way of the street is within the freeze area as defined.

(5) Boston proper means that portion of the City of Boston, Massachusetts, contained within the following boundaries: The Charles River and Boston Inner Harbor on the northwest, north, and northeast, the Inner Harbor, Fort Point Channel, Fitzgerald Expressway, and the Massachusetts Avenue Expressway access branch on the east and southeast, and Massachusetts Avenue on the west. Where a street or roadway forms a boundary, the entire right-of-way of the street is within the Boston proper area as here defined.

(6) Regional Administrator means the Administrator of Region I of the U.S. Environmental Protection Agency.

(7) Governor means the Governor of the Commonwealth or the head of such executive office of the Commonwealth as the Governor shall designate as responsible for carrying out specific provisions of this subpart.

(8) Commonwealth means the Commonwealth of Massachusetts.