The St. Johns - Springerville area consists of about 700 mi2 including Townships 9 through 12 North and Ranges 28 through 31 East in Apache Co., Arizona, and Townships 1 South through 3 North and Ranges 19 through 21 West in Catron Co., New Mexico (Figure 1). The graveled Salt Lake road between st. Johns and Salt Lake, New Mexico, and paved U.S. Highway 180 / 191 between st. Johns and Springerville, and U.S. Highway 60 between Springerville and Socorro, New Mexico, generally define the north, west, and south boundaries of the area. In December 1998, Ridgeway Arizona Oil Corporation (Ridgeway) reported that it had leased about 400,000 acres in the area in connection with its carbon dioxide (C~) project. Acreage is mostly state and private land in Arizona and mostly federal land in New Mexico. The St. Johns - Springerville area lies in the high plateau country of east-central Arizona. Elevations range from 5730 ft at St. Johns to 7810 ft at Coyote Peak to about 7000 ft at Springerville. The terrain is relatively flat with numerous low, grassy hills and patches of juniper and lesser patches of pinyon pine. The area around Springerville contains some of the finest high altitude grazing land in Arizona. The St. Johns - Springerville area lies in the rain shadow of the high, pine-covered Mogollon Rim and White Mountains. Average precipitation is about 11 inches per year, and is generally light, widespread and long-lasting snow in winter but spotty and brief thundershowers in the summer. The numerous unimproved access roads are frequently washed out and in many places turn into impassable heavy, sticky mud during the brief summer thundershowers and after snow melts. Carbon Dioxide in the St. Johns-Springerville Area, Apache County, Arizona Scale 1:100,000