Improved containment mats and systems of containment mats may include multiple adjoining mats with a top surface and a bottom surface. The multiple mats may provide a modular structural mat system that may be installed at a drill site, with multiple mats placed adjacent to each other with a lap joint connecting adjacent mats. A geotextile may be used to cover the lap joints and a coating applied to the geotextile. Such a system may provide containment of potential spills, a reliable working surface for drilling operations, and relatively fast and less expensive installation.