By Christopher D. Farrar, John M. Neil, and James F. Howle
U.S. GEOLOGICAL SURVEY
Water-Resources Investigations report 98-4217
Sacramento, California 1999

Figure 3. Configuration of A, permanent soil-gas sampler installations,
and B, monitoring-well site HSL-1 of ground-water monitoring well and
soil-gas samplers in the unsaturated zone, Mammoth Mountain, California.