Dominion’s Surry Nuclear Power Station urgently needed a new dredge material management area (DMMA). Its current one was nearly full, and its dredge channel, used for transporting materials and equipment on vessels along the James River to the station, must maintain a consistent water depth. Dominion retained Schnabel to support an accelerated DMMA design process that moved from concept to bidding in one month.

Typical per-dredge volumes for its 1,800-foot-long channel range from 100,000 to 150,000 cy of dredge materials. Like a dam, the DMMA is an engineered impoundment that can be subject to a breach. One of our tasks – performing a dam breach analysis and inundation study – helped determine the structure’s hazard classification in accordance with Virginia Department of Conservation and Recreation requirements. Using 2D analysis, we assigned a low-hazard classification, allowing the structure to be designed for a smaller storm, significantly reducing overall project risks and costs. We provided siting, planning, and design for this new 60-acre lined DMMA site and the two-mile temporary dredge line within Lawnes Creek for transfer of dredge effluent from the dredge site to the DMMA.

Prior to the site’s purchase, we provided geotechnical and environmental site evaluation to support due diligence efforts. Once purchased by Dominion, we provided comprehensive design-related project services including a flown LiDAR topographic survey; an ALTA survey; various environmental permitting support including Sections 401/404 and Section 106, wetland delineation, and the Chesapeake Bay resource protection area assessment; stormwater control design; Phase I, II, and III archaeological evaluation, including excavation and reinterment of historic human remains; view-shed analysis; and the final dredge pond design.

The project included the preparation of contractor bid specifications to support construction, and a public outreach component to address citizens’ concerns. During the one-year construction period, Dominion retained us to provide full-time construction observation of the contractor’s activities and quality assurance. We also provided environmental compliance services, including stormwater pollution prevention plan inspections every five days and coordination with various regulatory agencies related to site environmental permits. Follow-on services included design and environmental permitting to support the construction of a facility boat dock within Lawnes Creek, a tidal creek used for oyster leases.