At a military engineering depot in California, earlier consultants had performed a shallow soil gas survey as part of a groundwater contamination investigation. Their sampling depths were limited because the sampling probes were not capable of penetrating the deeper rocks and cobbles. Regulatory agencies had questioned the validity of the shallow soil gas data, claiming that the samples had been diluted by exposure to the atmosphere.

Kleinfelder used sonic drilling, a non-traditional drilling technique, to penetrate cobbles and collect soil gas at depth. The deep soil gas data results ended disputes about the validity of the soil gas data, and led to dismissal of the claims that the client was responsible for groundwater contamination.

On a related front, Kleinfelder is currently using sonic drilling methods as part of a dam instrumentation program for Creekside Dam No. 1 project near Canyonville, Ore. Over 900 feet of sonic drilling in complex embankment and foundation conditions will be completed and a system of over 30 vibrating wire piezometers will be installed. The dam and foundation instrumentation program will be part of an early warning system aimed at identifying any problems developing in the dam that could threaten an Interstate 5 underpass, a large campground and recreation complex at the toe of the dam along with nearby motels and residents.