At about 8:45 a.m. on Friday, July 6, a 52 year-old female backpacker staying in the Little Yosemite Valley backpacker's campground suffered partial thickness burns (2nd degree burns) to both her legs. After eating breakfast, the subject and her fellow backpackers prepared to wash their dishes by bringing a pot of water to boil. The group was using a single-burner backpacking stove, placed on top of a low stump. The pot of boiling water was accidentally spilled on the subject's legs, causing partial thickness burns to the subject's entire right knee and an estimated two-thirds of the circumference of the subject's left calf. Unfortunately, this incident was not a singular event this summer; multiple cases of burns occurring in park campgrounds have been treated at the Yosemite Medical Clinic.
http://www.nps.gov/yose/blogs/Partial-Thickness-Leg-Burns-in-Little-Yosemite-Valley.htm