RS-17-082, Redacted Dresden Nuclear Power Station, Units 1, 2 & 3, Revision 12 to Updated Final Safety Analysis Report, Chapter 02, Site Characteristics
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DRESDEN - UFSAR Rev. 4 2.1-1 2.1 GEOGRAPHY AND DEMOGRAPHY
2.1.1 Site Location and Description
2.1.1.1 Site Size and Location
The Dresden Nuclear Power Station site consists of approximately 953 acres located in the northeast quarter of the Morris 15' quadrangle (as designated by the United States Geological Survey [USGS]), Goose Lake Township, Grundy County, Illinois. The tract is situated in portions of Sections 25, 26, 27, 34, 35, and 36 of Township 34 North, Range 8 East of the third principal meridian. The site boundaries generally follow the Illinois River to the north, the Kankakee River to the east, a county road from Divine extended eastward to the Kankakee River on the south and the Elgin, Joliet and Eastern Railway right-of-way on the west, as shown in Figure 2.1-1.
A cooling lake, which was formed by constructing an impervious earth-fill dike, encompasses a storage area of approximately 1275 acres as shown on Figure 2.1-2. The lake extends north of Lorenzo Road from Dresden (Pequot) Road to the Santa Fe Railroad right-of-way to a line about 250 feet south of the Kankakee River. The lake is connected to the intake and discharge flumes of Units 2 and 3 by two canals (one intake and one discharge); each canal is about 11,000 feet long.
2.1.1.2 Location of the Units on the Site Unit 1 is located in the northeast quadrant of the site with an intake canal extending west from the Kankakee River and a discharge canal extending north to the Illinois River. Unit 1 was officially retired on August 31, 1984, but its major structures are still present and intact. Unit 2 is located on the site directly west of and adjacent to Unit 1. The location of Unit 3 is directly west of and adjacent to Unit 2. At this location, the units are situated approximately 0.5 miles from the south boundary of the site, 0.5 miles south of the center of the navigation channel in the Illinois River, and approximately 1 mile from the western boundary of the site. Refer to Drawing M-1 for a plan view of the property.
2.1.1.3 Site Ownership EGC is the sole owner of the entire 953-acre tract. This tract is subject only to an easement of the U.S. Government for an access road to the Dresden Island Lock and Dam, which is maintained and operated by the U.S. Army Corps of Engineers. The access road traverses the site from south to north approximately 0.8 miles west of the plant.
In addition to ownership of the tract and cooling lake, EGC also leases approximately 17 acres from the State of Illinois. This acreage is comprised of two narrow strips of river frontage located near the northeast corner of the site. The terms of the lease provide that these "buffer" strips shall remain idle. This parcel DRESDEN - UFSAR Rev. 5 January 2003 2.1-2 of property, which extends southeastward from the Dresden Lock and Dam, is not developed and is accessible only by foot. It is slightly depressed and provides drainage of the surrounding land. EGC does not exercise any control over this piece of property.
2.1.2 Exclusion Area Authority and Control
2.1.2.1 Exclusion Area The exclusion area boundary (EAB), which is common for all three nuclear units, has a radius of 0.5 miles (800 meters) and is shown on Figure 2.1-1. Section 100.3(a) of 10 CFR 100 requires that a reactor licensee have the authority to determine all activities within the designated area, including the exclusion and removal of personnel and property. No public highways or railroads transverse the EAB.
Through direct ownership, including mineral rights or a lease agreement with the State of Illinois, the licensee has total control of the entire area within the EAB with the exception of control over the Des Plaines and Kankakee rivers. As a result of this exception, arrangements have been made with the U.S. Coast Guard, through the Illinois Emergency Management Agency (IEMA) and the Illinois Department of Nuclear Safety (IDNS) for control of the water traffic in event of a plant emergency. This arrangement is documented in the Emergency Plan (E-Plan).
2.1.2.2 Access to the Site The units, including their intake and discharge canals, are completely enclosed by a security fence (see Drawing M-1) consisting of a 6-foot high chain link fencing surmounted by three strands of barbed wire. This fence also establishes the boundary for purposes of the Price-Anderson indemnity agreement and the nuclear liability insurance policies maintained. Access to the area is controlled at a security gate.
The frontage upon the Illinois and Kankakee rivers does permit access to the site by water. There are roads to both rivers which parallel the intake and discharge canals. A breakwater, ramp, and pier on the Illinois River are the only boat docking facilities. These facilities were used to bring in components for the nearby Braidwood Nuclear Station during its construction.
2.1.2.3 Other Activities on the Site Portions of the 953-acre tract outside the area occupied by the station are leased to a neighboring farmer for grazing cattle and growing field crops. Approximately 150 acres are used for grazing with appropriate fencing provided to control the approximately 75 head of cattle that may be present during the pasturage season. Field crop cultivation generally occupies about 300 acres. The lease has been DRESDEN - UFSAR Rev. 7 June 2007 2.1-3 modified with a clause which allows EGC to have "sole authority to determine the right of access and the right to be present in the area covered by this lease" when the GSEP is in effect.
Hunting is permitted on the site outside of the security fenced areas during legally prescribed seasons.
A guyed, structural steel microwave relay tower belonging to the International Bell Telephone System is located on the site approximately 1000 feet west-southwest of the reactor building. The equipment installed on the tower and in the small adjacent control building is automatically controlled, thereby requiring infrequent visits to the facility by telephone company maintenance personnel.
A guyed, structural steel meteorological monitoring tower is located approximately 3000 feet west of the reactor building. The tower serves multiple purposes; it has meteorological monitoring equipment attached at various elevations, and it is also employed as a microwave communications tower for several functions. The communications uses include transmission of line and switchyard information to the load dispatcher and two-way communications between the station (control room) and emergency facilities such as the following: Technical Support Center (TSC), Dresden; Emergency Operations Facility (EOF), Downers Grove mobile units and environmental monitoring
teams.
2.1.3 Population Distribution
2.1.3.1 Population Data
As part of the Systematic Evaluation Program (SEP) for Unit 2, a review has been conducted in accordance with Standard Review Plan (SRP), Section 2.1.3, "Population Distribution."
There is no resident population within the EAB. The transient population within the EAB of the nuclear station consists only of operating personnel, construction workers, visitors, and NRC inspectors. No changes are expected within the EAB.
The transient population in the vicinity of the station outside the EAB comprises workers employed by the various industries in the area and visitors to the many recreational facilities available.
The low population zone (LPZ) for the station is an area within an 8000-meter (4.97-mile) radius. The population within the 8000-meter radius area is approximately 12,000.
The nearest resident population within the LPZ is contained in a cluster of cottages along the west shore of the Kankakee River; the nearest line of cottages is just outside the EAB. The estimated population of this cluster of homes is approximately 400.
The other closest residences are widely separated in several directions from the station. A single residence is located approximately 0.6 miles southeast of the station on the east shore of the Kankakee River. To the northwest, approximately DRESDEN - UFSAR Rev. 7 June 2007 2.1-4 0.8 miles from the station, are a temporary construction office trailer and two permanent residences for engineers at the Dresden Island Lock and Dam. At the confluence of the Des Plaines and Kankakee rivers there is a new residential development that includes six houses from 0.8 to 1.0 miles from the station. Three individual residences are located along the Kankakee Bluffs on the north shore of the Des Plaines and Illinois rivers approximately 0.8 miles to the north-northwest, northeast, and east of the station, respectively.
The closest significant residential concentration of over 1000 residents is 3 to 4 miles northeast of the station along the Illinois River.
The nearest incorporated municipality is Channahon with a 2000 census population of 7344 people, substantially more than the reported 1990 population of 4266. Channahon is actively expanding by annexing adjacent properties that have been recently developed for residential subdivisions. A large tract of vacant land extending 2 to 3 miles northeast of the station has been annexed by the village of Channahon but not yet developed. Future expansion, however, is probable as the area near the confluence of the Du Page and De s Plaines rivers is developed.
The next closest incorporated municipality, Minooka, has its closest border approximately 3.5 miles north-northeast of the station. It has also been expanding. The present population according to the 2000 census is 7295, substantially more than the 1990 population of 2561.
Other significant unincorporated residential developments have been expanding in the strip-mined areas 4 to 5 miles southwest of the station, in a residential complex across U.S. Highway 6 from the industrial center 3.5 miles northwest of the station and along Aux Sable Creek 4.5 miles northwest of the station.
The 1990 population of other municipalities, including the population centers (containing more than 25,000 residents) within 50 miles of the station based on 1990 census data, is compared with the population data shown in the Final Environmental Statement (FES) (see Table 2.1-1).
The criterion that the nearest major population center must be over one and one-third times the distance of the LPZ radius (5 miles) is still being met. These residential concentrations do not appreciably alter the permanent population distribution patterns reported previously, except that the growth of the rural communities was greater than projected in the FES, whereas the population of most large cities located further from the station have declined.
2.1.3.2 Land Use The land to the north and west of the site is used principally for agriculture.
Adjacent to the site on the southwest side is the GE Morris Operations Facility (NRC Docket 50-268). It was originally planned as a spent fuel reprocessing facility but is now used for spent fuel storage. A description of the facility is presented in the application, as amended, and filed in the proceeding.
DRESDEN - UFSAR 2.1-5 The nearest boundary of the large Joliet Ammunition Plant (36,000 acres) is located approximately 2 miles east of the site and adjacent to a recreational area of about 2500 acres owned by the State of Illinois.
There are additional private recreational facilities such as gun clubs and picnic grounds scattered throughout the strip-mined areas south of the station. A small unnamed public park is also located 1.5 miles east of the station on the Des Plaines River. Public access is available to the Dresden Lock and Dam, and a public path parallels the Illinois and Michigan Canal which is 0.7 miles north of the station at its closest point. The recreational facilities are apparently being actively expanded and improved, and data on daily use indicate a substantial increase in recreationists in recent years. Major recreation facilities are listed in Table 2.1-2.
South of the site are some agricultural operations and a large abandoned strip mine. For a more detailed description of nearby industrial, transportation, and military facilities refer to Section 2.2. The Illinois Plan for Radiological Accidents (IPRA) describes nearby institutional facilities.
2.1.3.3 Summary The EAB of the Dresden Nuclear Power Station, as reported previously, has no permanent residents. Permanent population distribution around the station has not changed significantly; although, total 1990 census population within the 5-mile LPZ has increased to 8948 residents from 5090 reported in the FES. Industrial facilities and recreational facilities have also expanded, although their distribution is largely unchanged. The daily maximum transient population, including visitors to recreational facilities and workers employed by industries within 5 miles of the station is estimated to be approximately 15,200. The LPZ and population center distance specified for the site are in conformance with 10 CFR 100.
DRESDEN - UFSAR Rev. 7 June 2007 (Sheet 1 of 1)
Table 2.1-1 POPULATION CENTERS SURROUNDING THE STATION 1990 Population 2000 Population Distance from Station (mi) Direction from Station Morris, IL 10,270 19,114 7.5 WSW Coal City, IL 3,907 4,797 8 S Braidwood, IL 3,584 5,203 9 SSE Wilmington, IL 4,743 5,134 10 SE Joliet, IL 76,836 106,221 15 NE Aurora, IL 99,581 142,990 27 N Kankakee, IL 27,575 27,491 30 SE Chicago, IL 2,783,726 2,896,016 50 NE DRESDEN - UFSAR (Sheet 1 of 1)
Table 2.1-2
MAJOR RECREATIONAL FACILITIES NEAR THE STATION
Distance from Station (mi) Direction from Station Illinois, Kankakee, and Des Plaines rivers Adjacent Goose Lake State Park 1.0 SW Collins Lake 2.0 W Des Plaines Conservation Area 2.5 SE Empress Riverboat Casino 8-9 NE Lake Point Club 5-6 SSE
DRESDEN - UFSAR Rev. 12 June 2017 (Sheet 4 of 19)
Table 2.2-8 (Continued)
POTENTIALLY TOXIC CHEMICALS STORED AT FIXED FACILITIES WITHIN A 5-MILE RADIUS OF DRESDEN STATION
Company Distance to Dresden (mi) Compound
Weight Range (lb) Maximum per Vessel (lb)
Diversified Chemicals &
Propellants Co.,
CPC International 3.4 Chlorodifluoromethane (R-22) 6,565 Difluoroethane (R-152) 7,000 H{2} 1-Chloro 1,1-difluorethane (142 B) 7,000 Normal pentane 30,000 gal Isopentane 30,000 gal n-Butane 30,000 gal Propane 30,000 gal Methanol Dimethyl ether 10,000 Isopentane/isobutane blend 3,275 Ethylmercaptan Iso-butane 339,337 Propylene 209 N-pentane 365,695 Tetrafluoroethane 91
DRESDEN - UFSAR 2.5-1 2.5 GEOLOGY, SEISMOLOGY, AND GEOTECHNICAL ENGINEERING 2.5.1 Basic Geologic and Seismic Information 2.5.1.1 Geology A study of the geology of the Dresden site was made in 1965 by Dames and Moore, consultants in applied earth sciences, soil mechanics, engineering geology, and geophysics. The study was reported in Volume III, Section 4, of the Dresden Unit 2 Plant Design and Analysis Report (PDAR). The NRC reviewed the 1965 study as part of the Systematic Evaluation Program (SEP) Topic II-4.
The geological characteristics of the site, which were previously studied and determined to be suitable for Dresden Unit 1, were confirmed by the 1965 study. The load-bearing ca pability of the rock formation is significantly in excess of that necessary for the support of the units. The topographic (elevations) characteristics of the Dresden Station, particularly those for the location of Units 2 and 3, preclude possible movements (slides) of the plant structures into the Illinois River or earth slides from adjacent higher elevations on to the units.
The site is located just west of the area where the Des Plaines and Kankakee rivers flow together to form the Illinois River. The terrain is slightly hilly with a maximum relief at the site of about 25 feet. Regional relief is on the order of 200 feet. The site area is within the Central Lowland Physiographic Provence.
A thin (less than 10-foot) mantle of soil, mostly glacial drift, overlies bedroc k at the site. The upper unit of bedrock is the Spoon formation of the Pennsylvanian age (300 million years before present [MYBP]). The Spoon is a sandstone that varies in thickness beneath the site from 0 to 45 feet. A thin soil horizon is present below the Spoon overlying rocks of the Upper Ordovician (450 to 430 MYBP) Marquoketa formation. The Marquoketa consists of a 20- to 45-foot thick upper limestone member, the Fort Atkinson limestone, and a 70-foot thick lower shale member, the Scales shale. Below the Marquoketa formation are approximately 1000 feet of limestone, dolomites, and sandstones ranging in age from Middle Ordovician (450 MYBP) to Cambrian (570 MYBP).
These rocks lie on the Precambrian crystalline basement.
The Dresden site lies within the Central Stable Region of the North American Continent. This region extends from the Rocky Mountains to the Appalachian Plateaus and is relatively undeformed tectonically. It is characterized by a pattern of large basins, domes, and arches which formed throughout the Paleozoic Era (570 to 225 MYBP). The site is located on the northeast flank of one of these structures, the Illinois Basin. The north-northwest striking LaSalle anticlinal belt, a major structural element within the Illinois Basin, lies a few miles west of the site. The LaSalle anticline is a band of en echelon folds which formed during the Mississippian and Pennsylvanian periods (345 to 280 MYBP).
The northwest trending Kankakee Arch forms the northeastern bou ndary of the Illinois Basin and intersects the Wisconsin Arch to the North DRESDEN - UFSAR 2.5-2 2.5.1.2 Seismology The Dresden site area is placed in Zone 1 (zone of minor damage) on the seismic probability map of the 1958 Uniform Building Code. The August 1958 Seismic Regionalization map by Richter gives general predictions of probable maximum earthquake intensity and, recognizing that lines between the areas of
differing intensity are approximations only, shows the Dresden region as Modified Mercalli Intensity (MMI) VII to VIII.
Only a few earthquakes of significant intensity in Northern Illinois have been reported since 1800, and none has been accompanied by clear-cut surface faulting. A quake on May 26, 1909, caused moderate damage in Aurora, Bloomington, Chicago, and Joliet, and may have been of intensity MMI VII in the Dresden area. A quake on January 2, 1912, had a reported intensity of MMI VI at Aurora, Yorkville, and Morris, and probably was of similar intensity at the Dresden site location.
The engineering consulting firm of John A. Blume and Associates, San Francisco, was retained for advice on seismology; they consulted Dr. Perry Byerly, Oakland, California on the seismicity of the site region. The seismological studies indicated that the area of Northern Illinois and the actual Dresden site are seismically suitable. Nevertheless, it was considered appropriate to adopt a design approach which would assure the safety of Units 2 and 3 by preserving the ability to maintain the units in a safe shutdown condition in the event of a strong earthquake having a ground acceleration of 0.2 g. Seismic design motion is discussed further in Section 3.7.1.
2.5.2 Vibratory Ground Motion
Studies were conducted to determine the effects at the site of possible significant seismic events. The studies considered local and regional geology, seismology, and seismic history. The design basis is derived from the seismic design report of John A. Blume and Associates and is discussed further in Section 3.7.1.
2.5.3 Surface Faulting The Sandwich Fault zone is the largest fault in the site region. It is located on the north flank of the Ashton Arch, which merges to the north with the LaSalle anticlinal belt described in Section 2.5.1.1. The Sandwich Fault is oriented west-northwest and is about 90 miles long. It passes 6 miles north of the station. The fault zone is approximately 100 feet wide, dips nearly vertically, and rocks to the north of it are down-thrown with respect to rocks to the south. A maximum displacement of 900 feet is found 20 to 30 miles west of Chicago. This displacement decreases to 0 within 18 miles of Chicago.
Another fault which is interpreted to be a continuation of the Sandwich Fault zone carries the trend farther eastward but with the south side down with respect to the north side. The offset increases from 0 to as much as 100 feet to the east. The two faults have a scissor-like relationship to one another. The Sandwich Fault zone is DRESDEN - UFSAR 2.5-3 post-Silurian in age (younger than 395 MYBP) becau se Silurian rocks are o ffset. Rocks younger than Silurian have been eroded from the fault zone. Minor folds, faults, and evidence of warping of Pennsylvanian rocks within the region suggest some post-Pennsylvanian (younger than 280 MYBP) tectonic activity. Pleistocene drift has not been deformed by the fault, thus indicating no movement for at least the last several tens of thousand years. Minor faults found at the site have similar trends and senses of movement and are most likely related to the Sandwich Fault zone with similar time spans since the last movement.
2.5.4 Stability of Subsurface Material and Foundations Examination of cores from borings at the site and excavation for the construction of Units 1 and 2 show that all footings for major structures have a foundation of sound rock which eliminates the potential problems of soil consolidation and differential settlement. A very extensive survey and study of the underlying soil and rock was made prior to the construction of Unit 1, and an additional study was completed in 1965 for the application of Unit 2.
The generalized geologic column for the site consists of an upper layer of Pennsylvanian Pottsville sandstone of variable thickness of 40 to 50 feet. The next layer below is about 15 to 35 feet of Ordovician Marquoketa Divine limestone based on a 65-foot layer of Marquoketa dolomitic shale. The Ordovician system has a total thickness approaching 1000 feet, with the Cambrian system next below. Brecciated rock is found on some cross sections and is indicative of ancient faulting. The geologic evidence indicates that these faults are inactive.
Laboratory tests showed that unconfined ultimate compressive strength on boring samples ranged from 2000 to 15,000 psi on most samples. Laboratory wave velocity propagation tests showed 4000 to 15,000 ft/s.
In summary the geological characteristics of the site are suitable for Dresden Station. The load-bearing capacity of the rock formation foundation is significantly in excess of that necessary for the support of the plant structures.
2.5.5 Stability of Slopes The only slopes at the Dresden plant considered critical with regard to slope stability are those of the intake canal from the river to the crib house and of the discharge canal from the plant to the river.
The intake and discharge canals are about 56 feet wide and are cut into sandstone rock on an average of 13 feet to 25 feet, with near vertical side slopes. The rock top varies from elevation 508' to greater than 510'. The maximum height of soil above rock along the canals is about 6 feet. The overburden slopes are inclined at 3 feet horizontal to 1 foot vertical. The normal pool level in the canals is at elevation 505'; the maximum historic flood level prior to plant operation was at elevation 506.6'. In December 1982, the Dresden site was subjected to flood waters that exceeded 509 feet. The overburden slopes are above the canal water level and also lie above the water table (normal groundwater level between elevations +505 feet and 508 feet) and are thus normally dry.
DRESDEN - UFSAR 2.5-4 A "sliding wedge" slope stability analysis under safe shutdown earthquake (0.2 g horizontal acceleration) loading indicates a minimum factor of safety of 1.5 against failure of the intake or discharge canals.
However, even if the overburdened slopes failed and this material moved into the canal, there would still be an ample water supply in the intake canal for use in station operation.
The rock into which the canals are cut is sound and capable of maintaining a stable vertical cut under earthquakes or other events. The rock, locally referred to as the Pottsville sandstone, is composed predominantly of cemented sub-angular fine-to- medium grains of quartz containing varying amounts of mica. No evidence of faulting exists in the sandstone at the site, but there are occasional vertical joints. Laboratory compressive strength tests on the sandstone indicate strengths of the rock in excess of 3000 psi. Therefore, slope stability is not a safety concern for Dresden Station.
2.5.6 Embankments and Dams
2.5.6.1 Dresden Lock and Dam
The Dresden Lock and Dam is maintained and operated by U.S. Army Corps of Engineers as part of the Illinois River Waterway. The design of the lock and dam was started following Worl d War I by the State of Illinois. The Dresden Lock and Dam was to be the first of a series of dams and locks to permit navigation on the Illinois River. Construction was started in 1925; however, the state's funds were soon depleted. The federal government assumed responsibility and construc tion was completed in 1932.
In discussions with the Corps of Engineers, the design of the dam and lock was not based on any seismic criteria as is used today. The dam and lock were designed to withstand the large forces due to the mass movement of ice flows from the Des Plaines and Kankakee rivers, floods during periods of heavy runoff, and the impact forces of runaway tows. It should be remembered that the problems of the large movement of ice were of real concern in the 1920's, prior to the industrialization of the waterway above the dam. The dam consists of 11 heavily reinforced concrete piers 10 ft. x 45 ft. at the top and 10 ft. x 60 ft. at the bottom with the taper on the downstream side. Each pier is socketed 5 feet into bedrock and anchored. Between the piers are concrete gravity section rollaways. Above these are Tainter Gates, which control pool level, supported from the piers. The dam is anchored to the rock rising to the Kankakee Bluffs at the north end and the lock structure on the south. The lock walls are 10 feet wide at the top, 20 feet wide at the bottom, and 800 feet long. The lock width is 110 feet.
Since the dam and lock are of major importance to the Chicago region, and its function is the responsibility of the Corps of Engineers, an evaluation of its adequacy to seismic activity could only be made by the corps. Commonwealth Edison does not have access to the detailed drawings or design calculations. However, the design of Dresden Station accounts for the potential catastrophic failure of the dam and lock, as described in Section 9.2.5.3.