§  73.609   Zones.

   (a) For the purpose of allotment and assignment, the United States is
   divided into three zones as follows:

   (1) Zone I consists of that portion of the United States located within
   the confines of the following lines drawn on the U.S. Albers Equal Area
   Projection Map (based on standard parallels 291/2DEG and 451/2DEG;
   North American datum): Beginning at the most easterly point on the
   State boundary line between North Carolina and Virginia; thence in a
   straight line to a point on the Virginia-West Virginia boundary line
   located at north latitude 37DEG49' and west longitude 80DEG12'30";
   thence westerly along the southern boundary lines of the States of West
   Virginia, Ohio, Indiana, and Illinois to a point at the junction of the
   Illinois, Kentucky, and Missouri State boundary lines; thence northerly
   along the western boundary line of the State of Illinois to a point at
   the junction of the Illinois, Iowa, and Wisconsin State boundary lines;
   thence easterly along the northern State boundary line of Illinois to
   the 90th meridian; thence north along this meridian to the 43.5DEG
   parallel; thence east along this parallel to the United States-Canada
   border; thence southerly and following that border until it again
   intersects the 43.5DEG parallel; thence east along this parallel to the
   71st meridian; thence in a straight line to the intersection of the
   69th meridian and the 45th parallel; thence east along the 45th
   parallel to the Atlantic Ocean. When any of the above lines pass
   through a city, the city shall be considered to be located in Zone I.
   (See Figure 1 of § 73.699.)

   (2) Zone II consists of that portion of the United States which is not
   located in either Zone I or Zone III, and Puerto Rico, Alaska, Hawaiian
   Islands and the Virgin Islands.

   (3) Zone III consists of that portion of the United States located
   south of a line, drawn on the United States Albers Equal Area
   Projection Map (based on standard parallels 29.50 and 45.50 North
   American datum), beginning at a point on the east coast of Georgia and
   the 31st parallel and ending at the United States-Mexican border,
   consisting of arcs drawn with a 241.4 kilometer (150 mile) radius to
   the north from the following specified points:
       North latitude West longitude
   (a)    29DEG40'00"    83DEG24'00"
   (b)    30DEG07'00"    84DEG12'00"
   (c)    30DEG31'00"    86DEG30'00"
   (d)    30DEG48'00"    87DEG58'30"
   (e)    30DEG00'00"    90DEG38'30"
   (f)    30DEG04'30"    93DEG19'00"
   (g)    29DEG46'00"    95DEG05'00"
   (h)    28DEG43'00"    96DEG39'30"
   (i)    27DEG52'30"    97DEG32'00"

   When any of the above arcs pass through a city, the city shall be
   considered to be located in Zone II. (See Figure 2 of § 73.699.)

   [ 28 FR 13660 , Dec. 14, 1963, as amended at  33 FR 15422 , Oct. 17, 1968;
    50 FR 23697 , June 5, 1985;  51 FR 44070 , Dec. 8, 1986]