On March 24, 2007, at 1050 mountain daylight time, a Beech 200, N771HC, piloted by an airline transport pilot, sustained substantial damage when it struck a snow bank while landing at Angel Fire, New Mexico. Instrument meteorological conditions prevailed at the time of the accident. The flight was being conducted on an instrument flight rules flight plan under the provisions of Title 14 Code of Federal Regulations Part 91. The pilot was not injured. The cross-country flight originated at Oklahoma City, Oklahoma, and was en route to Angel Fire, New Mexico. According to the pilot, he was performing the RNAV approach on runway 17 (8,900 feet by 100 feet, asphalt). He reported his position on the common traffic advisory frequency (CTAF)(122.8 MHz) at 20 miles north, 10 miles north, and on a three mile final. About two miles from the approach end of the runway the pilot saw a snow plow on the northern end of the runway moving further north. The pilot maneuvered the airplane laterally to avoid over-flying the snow plow, and selected a touch down point 1,000 feet beyond the snow plow. Pictures of the accident airplane and runway environment, taken immediately after the accident, depict a swath of unplowed snow in the middle of the runway. During the landing roll, the left wing contacted the swath of snow. The airplane yawed about twenty-five degrees to the left and departed the runway environment. The airplane struck a runway light and the nose landing gear collapsed. The main longeron had a 1.5 inch hole and the forward bulkhead was buckled. An examination of the airplane's systems, conducted by the FAA, revealed no anomalies. According to the driver of the snow plow, he was plowing the runway and had a hand-held Unicom radio with him. He started plowing the west side of the runway toward the south, but the snow became too heavy for the plow about half way across the runway. The driver then started to plow the east side of the runway toward the north with the intention of plowing the middle section later. The driver reported the ground visibility at the time to be approximately one half mile to one mile. The driver saw the airplane on final but had not heard any position reports from the airplane on his radio. The driver turned to the west and the airplane maneuvered to the east to avoid the plow. The driver did not see the airplane again until he began plowing snow toward the south end of the runway. The driver drove down to the accident site to see if the pilot was injured. No NOTAMS were issued for snow removal activity or runway conditions. An AWOS-3 (Automated Weather Observation System) operated by North American Aviation Weather, located on Angel Fire Airport, at an elevation of 8,380 feet msl (mean sea level), issued a weather report at 1045 reported, visibility, 7 statute miles; precipitation, light snow; sky condition, scattered at 700 feet, broken at 1,900 feet, overcast at 3,400 feet; temperature, 1 degrees Celsius (C); dewpoint, 1 degrees C; altimeter, 30.01inches. The closest official weather observation station was Taos Regional Airport (KSKX), Taos, located 18 nautical miles (nm) west of the accident site. The elevation of the weather observation station was 7,091 feet msl. The routine aviation weather report (METAR) for KSKX, issued at 1055, reported, winds, 220 degrees at 6 knots, visibility, 10 statute miles; sky condition, broken at 300 feet, overcast at 700 feet; temperature 2 degrees Celsius (C); dewpoint, 1 degrees C; altimeter, 30.03 inches.