(a) Name. The name of the viticultural area described in this section is “Walla Walla Valley.”

(b) Approved maps. The appropriate maps for determining the boundaries of the Walla Walla Valley viticultural area are two U.S.G.S. maps, in the scale 1:100,000. They are entitled:

(1) “Walla Walla,” Washington-Oregon, 1980

(2) “Pendleton,” Oregon-Washington, 1983

(c) Boundaries. The Walla Walla Valley viticultural area is located within Walla Walla County in Washington State and Umatilla County in Oregon. It is entirely within the Columbia Valley viticultural area. The boundaries are as follows:

(1) The beginning point is on the Walla Walla quadrangle map, in T8N/37E, at the point where the 2,000 foot contour line intersects with an unnamed light duty road approximately 250 feet east of U.S. Highway 12 in Minnick, Washington (on maps measured in metric units, this elevation is between the 600 and 650 meter contour lines),

(2) Then the boundary goes northwest in a straight line for 7 kilometers (km), until it intersects with a power line that runs between T8N and T9N,

(3) Then the boundary follows the power line west for 8 km, where it diverges from the power line and goes west-southwest in a straight line for approximately 33 km to the intersection of 2 unnamed light duty roads in the area marked Ninemile Canyon in the southwest corner of T8N/R33E,

(4) Then the boundary goes south-southwest in a straight line approximately 8 km, until it reaches U.S. Highway 12, about 2.5 km east of Reese, Washington,

(5) Then the boundary goes south in a straight line for approximately 8 km, crossing the Washington-Oregon state line and moving onto the Pendleton U.S.G.S. map, where it meets the 450 m contour line in T6N/R32E, near an unnamed peak with an elevation of 461 m,

(6) Then the boundary follows the 450 m contour line in a generally southeasterly direction until it intersects Dry Creek in T4N/R35E,

(7) Then the boundary goes southeast along Dry Creek (Oregon) until it reaches the 2000 foot contour line,

(8) Then the boundary follows the 2000 foot contour line in a generally northeasterly direction, crossing the Oregon-Washington state line and returning to the Walla Walla U.S.G.S map, until it reaches the point of beginning.