FSAR: Section 2.5 Geology, Seismology, and Geotechnical Engineering 2.5 GEOLOGY, SEISMOLOGY, AND GEOTECHNICAL ENGINEERING {This section of the U.S. EPR FSAR is incorporated by reference with the following supplements. The summary includes a synopsis of FSAR Section 2.5.1 through Section 2.5.5, including a brief description of the site, investigations performed, results of investigations, conclusions, and identification of the organization that performed the work. This section is intended to demonstrate compliance with the requirements of paragraph (c) of 10 CFR 100.23, "Geologic and Seismic Siting Criteria" (CFR, 2007a). Regulatory Guide (RG) 1.208, "A Performance-Based Approach to Define the Site-Specific Earthquake Ground Motion", (NRC, 2007a) is the primary guidance document for the development of the site Probabilistic Seismic Hazard Analysis (PSHA) and Ground Motion Response Spectrum (GMRS). The terms site region, site vicinity, site area, and site are used in this section to describe the specific areas of investigation. These terms correspond to the following areas: 1. The site region is that area within 200 miles (322 km) of the site location. 2. The site vicinity is that area within 25 miles (40 km) of the site location. 3. The site area is that area within 5 miles (8 km) of the site location. 4. The site is that area within 0.6 mile (1 km) of the site location. SUMMARY The proposed Bell Bend Nuclear Power Plant (BBNPP) site is located south and west of the existing Susquehanna Steam Electric Station (SSES) in Salem Township, Luzerne County, Pennsylvania. The BBNPP site is found approximately 5 mi (8 km) northeast of the Borough of Berwick, Pennsylvania, and 1.5 mi (2.4 km) to the north and west of the north branch of the Susquehanna River. The major metropolitan centers closest to the site include: Wilkes-Barre, located 19 mi (31 km) to the northeast; Allentown, PA, approximately 50 mi (80 km) to the southeast; and Harrisburg, PA, which is approximately 70 mi (100 km) to the southwest. The BBNPP Owner Controlled Area (OCA) is 882 ac (357 ha). The BBNPP site occupies an area of 424 acres (172 hectares) within the OCA. The BBNPP is not within the Exclusion Area Boundary for SSES Units 1 and 2. For the establishment of the horizontal datum, Pennsylvania State Plane Coordinate System (North Zone), North American Datum of 1983 (NAD 1983) is utilized. For the establishment of the vertical datum, North American Vertical Datum of 1988 (NAVD 88) is utilized, unless stated otherwise. FSAR Section 2.5 provides information on the seismic, geologic, and geotechnical characteristics of the site and the region surrounding the site. The purpose of this information is to permit an adequate evaluation of the proposed site, to support evaluations performed to estimate the site-specific ground motion response spectrum (GMRS), and to permit adequate engineering solutions to actual or potential geologic and seismic hazards at the proposed site. Details of the studies and investigations performed as well as the findings and conclusions are presented in Section 2.5.1 through Section 2.5.5. BBNPP 2-1 Dec 2012 © 2007-2012 UniStar Nuclear Services, LLC. All rights reserved. Supplement COPYRIGHT PROTECTED FSAR: Section 2.5 Geology, Seismology, and Geotechnical Engineering The primary conclusions of Section 2.5 are as follows: 1. Section 2.5.1 Basic Geologic & Seismic Information - The site lies in a stable geologic region, and no geologic or man-made hazards are identified within the site area. The site is located in a region that has experienced only infrequent minor earthquake activity, with only 5 seismic events detected within a 50-mile (80-km) radius of the site.” 2. Section 2.5.2 Vibratory Ground Motion - A PSHA was developed in accordance with Regulatory Guide (RG) 1.208 (NRC, 2007a), using: (1) the EPRI/DOE/NRC (2012) Central and Eastern United States (CEUS) Seismic Source Characterization (SSC) model and (2) the EPRI (2004, 2006a) ground motion model. Based on the PHSA, deaggregation was carried out to identify controlling earthquakes and associated response spectra. The controlling earthquakes were used along with a site geotechnical model to perform site response analysis. The site response was combined with the uniform hazard response spectra (UHRS) from the PSHA according to Approach 2B of NUREG/CR–6728 (McGuire, 2001) to obtain hazard-consistent UHRS at the surface. The surface UHRS were then used to develop a performance based Ground Motion Response Spectra (GMRS) following RG 1.208. 3. Section 2.5.3 Surface Faulting - The site vicinity exhibits little evidence of faulting and all of it is non-capable. In addition, a targeted field investigation for the site vicinity discovered no evidence of paleoliquefaction features. 4. Section 2.5.4 Stability of Subsurface Materials and Foundations - Subsurface investigations concluded that the site analysis was bounded by the U.S. EPR FSAR for settlement, bearing capacity, hydraulic gradient and that the subsurface bedrock materials are stable with no potential for soil liquefaction. The Nuclear Island will be founded on either the Mahantango Formation or concrete fill. 5. Section 2.5.5 Stability of Slopes - The site exhibits limited natural slopes and the only permanent slopes are those for the Essential Service Water Emergency Makeup System (ESWEMS) Retention Pond. All permanent and temporary slopes are shown to have adequate stability safety factors. Additional details are summarized below. Basic Geologic and Seismic Information Regional Geology The BBNPP site lies within the Appalachian Mountain Section of the Ridge and Valley Province that consists of long, narrow ridges and broad to narrow valleys exhibiting moderate to very high relief. These ridges and valleys are a direct result of lithologic disparities in erosional resistance and the folded and faulted structures developed in the geologic past, when the mountains were built, during the Alleghanian Orogeny. This Province is primarily a zone containing Cambrian to Pennsylvanian rocks that were folded and faulted during the Alleghanian Orogeny that occurred during late Pennsylvanian through Permian times, nearly 300 million years ago. In addition to the geologic events that affected the entire Ridge and Valley Physiographic Province, three glacial advances affected the site vicinity during the Pleistocene Epoch. BBNPP 2-2 Dec 2012 © 2007-2012 UniStar Nuclear Services, LLC. All rights reserved. Supplement COPYRIGHT PROTECTED FSAR: Section 2.5 Geology, Seismology, and Geotechnical Engineering The BBNPP site region is located in a stable continental region (SCR) characterized by low rates of crustal deformation with no active plate boundary conditions. Beyond the site region, features or areas with repeated large magnitude (moment magnitude, M, equal to or greater than 6.5) earthquakes (RLMEs) are documented. Those with a potential impact on seismic hazard at the site are included in the PSHA. Site Geology Significant surface and subsurface investigations were conducted for the BBNPP site area foundation investigation, including field surveys, drilling, and geophysical exploration. Additional information was obtained from the SSES FSAR (SSES FSAR, 2003). The site is adjacent to the Susquehanna River near the southern edge of glaciation in Pennsylvania. The BBNPP site area is located within the Susquehanna Lowland Section of the Ridge and Valley Physiographic Province which is bordered by the Anthracite Valley Section to the west and north, the New England Province to the east, and the Piedmont and Blue Ridge Provinces to the south. The site area is underlain by folded Late Silurian, Devonian, and Early Mississippian formations. More specifically, the site bedrock is Upper Devonian Mahantango Formation. The most recent geologic influence on the site is the Wisconinan glaciation that deposited glacial materials (including kame terrace, moraines and outwash) on the bedrock surface in a layer approximately 40 feet thick. The topography within 5 mi (8 km) of the site consists of low to moderately high, linear ridges and valleys that primarily follow structural trends. Local elevations range from about 260 ft (79 m) to nearly 2,368 ft (722 m). The BBNPP is constructed at a final grade elevation of 719 ft (219 m) and is set back approximately 8,000 ft to 10,000 ft (2,438 m to 3,048 m) from the River bank. The local geologic formations were subjected to a series of mountain-building episodes, including the Grenville, Taconic and Alleghanian orogenies. The local structure of the Ridge and Valley Province was imparted to the area during the Alleghanian Orogeny at the end of the Permian Period, nearly 250 million years ago. The site geologic history has been quiet since the end of the Permian. At that time the local portion of the crust became more stable and tensional stresses predominated through the Cretaceous Period. The only disturbance of this quiet state was the advance of several ice sheets in the Pleistocene. However, because the site is located at the extreme southern limit of the glaciated area, the ice sheets were at their thinnest and any crustal depression or subsequent rebound from the ice load has been minimal. Geologic studies to determine the site structural characteristics were performed utilizing data obtained from site borings and geophysical surveys. In addition, bedrock exposures were mapped throughout the site area. A thorough search for faulting and detailed mapping of excavations was also performed. The site occupies a position on the northern limb of the northeast end of the Berwick Anticline. A pair of faults has been mapped near the axis of the anticline, but they are related to the Alleghanian Orogeny, and are not active today. No geologic hazards were identified during either investigation. The site is located in a region that has experienced only infrequent minor earthquake activity, with only 5 seismic events detected within a 50-mile (80 km) radius of the site.