Landfill gas project: helium soil-gas investigations. Final technical report

A series of preliminary helium soil gas surveys at a landfill site in DuPage County, Illinois, were conducted as part of a larger program to investigate the influence of meteorological parameters and, eventually, gas recovery operations on the production, transport, and migration of gases at landfill sites. The first survey determined the overall distribution of helium at the landfill and served as a guide to establish fixed stations for later surveys. The second survey monitored the variation of helium concentrations with time to view the effect of meteorological influences. From the helium data higher concentrations of landfill-produced gases were inferred to be located near the flanks of the landfill. The surface manifestations of gas were very localized, occurring in discrete areas of 100 m/sup 2/ or less. Fracture systems, developed by the settling landfill, control the near surface release of the gas and increase the local permeability permitting greater atmospheric dilution of the soil gases than at other areas of the landfill. 5 refs., 2 figs., 3 tabs.