In 2008, Great Basin National Park invited volunteers to come to the park and visit Lehman Cave, for free. The catch: they had to remove lint from the cave's walls. They had 10 takers, who removed eight pounds of material. But, this year, another "lint camp" attracred 37 volunteers, most of them under 25.
The crews picked lint from cave formations and walls along 600 feet of passage and treated algae accumulations near lights.
According to park officials, "Lint is introduced to the cave environment by the approximately 40,000 people who enter the cave each year. Lint is composed of fibers, hairs, skin cells, dust, and other foreign particles. Lint can become cemented into cave formations, causing discoloration or even dissolution of natural cave surfaces. Lint also acts as an artificial food source, potentially causing imbalances in cave biota communities."
The volunteers also cleared two tons of garbage that tourists had left in the cave. The volunteers had to bring their own supplies (including sleeping bags and cooking utensils) and provide their own lunches. But in exchange for their work, they received training and tours of the caves, which have been a tourist attraction since they were discovered in the 1880s.