On November 8, 1994 at 1330 Alaska standard time, a wheel equipped Piper model PA-12 airplane, N7599H, registered to and operated by a student pilot, nosed over during the taxi from a landing at a remote landing site approximately 10 miles north of Drift River. The coordinates of the accident site are 60'40"7N X 151'57"W. The 14 CFR Part 91 instructional flight last departed Kenai, Alaska at 1320, and the intended destination was the site of the mishap. The pilot, the sole occupant, was not injured, and the airplane sustained substantial damage. The pilot reported that visual meteorological conditions prevailed and that there was no flight plan on file for the flight. On the morning of November 21, 1994, the pilot visited the NTSB NW Field Office. The pilot told the NTSB investigator-in- charge that during the post landing taxi, he inadvertently maneuvered the airplane onto a sunken part of the landing strip and the airplane nosed over. The damage to the airplane included the two outboard ribs, and the tip bow on the left wing. Verification that an accident had occurred was not confirmed until the pilot's visit to the NTSB office. In the pilot/operator report submitted by the pilot, he described the landing area as snow covered grass. The length of the landing area was 500 feet long and 30 feet wide. The pilot indicated that he had accumulated 200 flight hours, 175 of which were in the accident aircraft make and model.