A brief history of E.S. Babcock & Sons, Inc. Laboratories. E.S. Babcock & Sons (ESB) California Environmental Testing Laboratories is one of the premier facilities in California for analytical testing. Our location in Riverside, California, the heart of the Inland Empire, offers a convenient solution to government and corporate clients as well as individual property owners. We provide testing for drinking water, wastewater, groundwater, storm water, and hazardous materials. Perchlorate testing, Low-Level Hexavalent Chromium testing, NDMA testing, UCMR 3 testing, and Field Sampling are just a few of the services we specialize in.