The project objectives are to improve the understanding of (drilling fluid) fiber sweeps, develop fiber sweep systems that improve hole cleaning in UDW drilling operations, minimize hole cleaning related problems, develop models and correlations to predict fiber sweep performance and optimization, recommend fiber sweep best practices, reduce drilling costs and improve operational safety, and develop sweep technology that minimizes the impacts of drilling on the natural environment. The study will deliver formulations of stable fiber containing sweep fluids, an experimental database describing hole cleaning performance of fiber sweeps, correlations and mathematical models that are useful for designing and optimizing fiber sweep applications, and recommendations and guidelines for field operations.