Markets Served Civil The diverse needs of civil work require both deep knowledge of solids control and agile management. CST customers work with a single project manager from start to finish. Oil & Gas The CST corporate office overlooks some of the densest oil fields in California & the world. World class producers work with Clean Slurry to maximize efficiency in their operations. Hydro Excavation Hydro excavation and vacuum truck firms are using Clean Slurry separation plants to reduce costs and undercut the competition. These plants are tailored to customer needs.