Environmental Dredging

Sevenson’s niche in the CCR Closure market is utilizing our Dredging, Dewatering,  Wastewater Treatment (WWT) & In-Situ Stabilization (ISS) Services

Sevenson has been working on Coal Ash Closures since 2009

Our coal ash closure experience started in 2009 at the TVA Kingston spill where we dredged and managed +2.5MCY of CCR from the Emory River. On large complex closure projects Sevenson will partner with other contractors and engineers to come together as a team to safely and efficiently complete closure requirements.

We utilize our full inventory of mechanical and hydraulic dredges, pumps, piping, tanks, desanding/scalping units, filter presses, centrifuges, and other essential equipment for supporting routine and complex CCR Closure Projects that require dredging/dewatering. Additionally, Sevenson owns, operates, and maintains a full range of equipment and resources to provide on-site water treatment services in support of dredging/dewatering and field remediation operations.

Sevenson’s ability to perform treatability studies for treatment applications, facilitates the development of on-site treatment systems which can be efficiently mobilized, assembled, and placed into operation. In-house technical/engineering personnel also support treatment system operations, as well as provide technical consulting in the event site conditions change. In addition, Sevenson has the in-house expertise to construct permanent water treatment plants in accordance with engineered specifications.

Through treatability studies, project schedules may be condensed at reduced costs as well as enable Sevenson to engage early with the owner and engineer to safely and efficiently configure dredging, dewatering, wastewater treatment, and stabilization/solidification systems to meet regulatory requirements and timelines. 

Sevenson has also been providing construction, fly ash management, and industrial services to utility companies on an ongoing basis since 2003. Services include:

• Fly ash management
• Excavation, transfer and placement into onsite landfill
• Management of onsite landfills includes compaction, grading, erosion control, water run on / run off collection and containment, installation of daily cover, and elevation survey
• Continuous dust control application
• General site restoration
• Vacuum truck services
• Pumping systems services
• Dredging and liquids/solids separation services using filter presses