- At the Eric Schmitz Corporation, we do soil testing as it relates to private onsite septic systems. Testing for soil contaminates, and building suitability is not included in our line of work. Seek out engineering firms for these types of testing. Our surveying services are limited to the smaller jobs. We specialize in house stakeouts, lot surveys & planning, simple land divisions, condominium ...www.ericschmitzcorp.com