When natural gas leaks from a subsurface pipeline, a ground cover of water/snow saturation, asphalt paving or a combination of these can cause the gas to migrate away from the leak site up to three to four times farther than through dry soil, a new study has found. When natural gas leaks from a subsurface pipeline, a ground cover of water/snow saturation, asphalt paving or a combination of these can cause the gas to migrate away from the leak site up to three to four times farther than through dry soil, a new study has found. Earth Sciences Environment Phys.org – latest science and technology news stories