On August 19, 1994, at 2000 Alaska daylight time, a tundra tire equipped Helio Courier model H295 airplane, N6DB, owned and operated by the pilot-in-command, dba Pyxis Ltd., collided with a marmot hole during the landing rollout at a remote landing site on the upper Aichilik River, approximately 80 miles northeast of Arctic Village, Alaska. The commercial certificated pilot, the sole occupant, was not injured, and the airplane sustained substantial damage. The pilot reported that the flight was conducted under CFR Part 135 for the purpose of checking on sheep hunters. The flight last departed Fort Yukon, Alaska, at 1830 and the intended destination was the remote strip. Visual meteorological conditions prevailed in the area and a VFR flight plan was in effect with the Fairbanks Flight Service Station. The pilot indicated that he was landing on a 700 foot long tundra bench with a load of fuel and supplies for the hunters. During the landing roll, the left main wheel struck a hole that was not visible from the air. The collision flattened the left tire and the airplane ground looped. The airplane received damage to the left wing and tail wheel assembly.