Nine Mile Point Unit 3 Site Characterization

UniStar Nuclear is examining the Nine Mile Point site in Oswego, New York for the proposed contruction of a 1,600 MWe AREVA APR reactor. The characterization of the site is required to determine detailed geological and geotechnical characteristics of the site for the detailed design of the reactor complex and to support the submission of the Combined Operating License Application (COLA) to the U.S. Nuclear Regulatory Agency in October 2008.

GEI was responsible for the design of the site characterization program, its execution, including field and laboratory-based studies, and the preparation of documentation to support the detailed engineering of the facility and the COLA. Our field program consisted of over 60 borings up to 250 feet deep for installation of groundwater wells, obtaining geotechnical data, and seismic surveys. Over 17,000 feet of seismic survey on land and 41,000 feet off shore was performed to determine depth to bedrock and to look for potential faults or zones of weakness. Various hydraulic tests were conducted in some of the boreholes to determine the site bedrock hydrological conditions. Approximately 50 borings, 7,000 feet deep, were drilled off shore to characterize the potential route of the intake/discharge tunnels into Lake Ontario.

The results of our field program and laboratory testing were used to determine seismic velocities and geotechnical properties, to determine load bearing and material stability properties for foundation design, and to support the detailed design of the off shore tunnels.

Our success was in part due to well written work plans and SOPs, continuous presence in the field of experienced management, clearly defined chains of responsibility and communication with our team and clients, maintaining a consistent staff throughout the project, integrating our subcontractors into planning and encouraging continual feedback, creation of a Technical Assistance Group of NRC recognized experts to refine the Probabilistic Seismic Hazardous Assessment (PSHA).

GEI also stressed constant communication with both AREVA and UniStar to seek input, to provide advice, and to align expectations with scope and schedule as the project was performed on a very compressed schedule. As a result, many of GEI’s milestone activities, such as each of the two field phases, and the FSAR sections were delivered to the client ahead of schedule.