ML23349A149
| ML23349A149 | |
| Person / Time | |
|---|---|
| Site: | Hermes File:Kairos Power icon.png |
| Issue date: | 12/15/2023 |
| From: | Kairos Power |
| To: | Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML23349A147 | List: |
| References | |
| KP-NRC-2312-001 | |
| Download: ML23349A149 (1) | |
Text
KP-NRC-2312- 001
Enclosure 1 Changes to PSAR Chapter 2 (Non-Proprietary)
Preliminary Safety Analysis Report Site Characteristics
As shown in Figure 2.1-2, the site is adjacent to Poplar Creek and 0.4 mile (0.6 kilometer [km]) from the Clinch River arm of the Watts Bar Reservoir. Poplar Creek is a tributary of the Clinch River arm of the Watts Bar Reservoir. Figure 2.1-2 shows prominent natural and man-made features within approximately 5 miles (8 km) of the site. The distance and direction from the sites center point of the safety-related area to major nearby features are as follows (Reference 1):
- Oak Ridge National Laboratory (ORNL) (4.8 miles)
- Clinch River Nuclear Site (3.6 miles)
- Interstate 40 (4.9 miles)
- Railroads (Heritage Railroad Corporation [1,132 feet], Norfolk Southern Railway Company [3.5 miles])
- Poplar Creek (0.2 miles)
- Clinch River arm of the Watts Bar Reservoir (0.4 miles)
- Duct Island (0.6 miles)
- Hermes Non-Power Reactor (proposed, 0.1 miles)
The region in which the site is located is known as the Great Valley of East Tennessee, which is comprised of valleys at elevations of around 800 feet above mean sea level and ridges around 1,000 feet above mean sea level or higher. The area is situated between the Cumberland Mountains, approximately 23.5 miles (38 km) to the northwest, and the Great Smoky Mountains approximately 31.6 miles (51 km) to the southeast. The area is characterized by forest, streams and reservoirs fragmented by urban development and agriculture. Part of the Ridge and Valley Province of East Tennessee, the site is located to the west of Poplar Creek on a gently rolling valley between Black Oak Ridge and Pine Ridge (Reference 4). Knoxville Tennessee is the nearest major metropolitan area, located approximately 25 miles (40 km) east of the site (Reference 5). Major transportation corridors in the region are Interstate 40 (I-40, the major east-west interstate highway located south of the site) and Interstate 75 (I-75, which travels in a north-south direction). I-40 and I-75 intersect approximately 9.5 miles (15.3 km) east-southeast of the site.
Outside the City of Oak Ridge, which includes the ORNL and the site, the surrounding land uses are generally residential and agricultural in nature, used primarily for single-family residences and small farms. Popular recreational activities in the area include fishing, hunting, boating, water skiing, and swimming (Reference 5).
Figure 2.1-2 shows the highways, railways, and waterways that traverse or are close to the site.
Figure 2.1-3 illustrates the topography within the vicinity of the site. The finished site grade elevation is approximately 765 feet North American Vertical Datum of 1988 (NAVD 88). The site and adjacent ground within a radius of approximately 0.5 miles is flat. Topographic elevations range from approximately 1,525 feet (464.8 meters) NAVD 88, to approximately 737 feet (224.6 meters) NAVD 88 to the east of the site. Therefore, the topography within a 5-mile radius ranges from approximately 28 feet below to approximately 760 feet above the site grade elevation (Reference 7).
The tallest buildings to be constructed at the site are the Reactor Buildings, which at their highest point are approximately 90 feet above the site grade level.
2.1.1.2 Boundary and Zone Area Maps The reactors are located within the Reactor Buildings shown on Figure 2.1-3. Figure 2.1-3 shows the site and exclusion area boundary (EAB) with respect to the reactor locations. In accordance with 10 CFR 20.1003, the site boundary defines the area owned, leased, or controlled by the licensee. In accordance with 10 CFR 100.3 and ANSI/ANS-15.16-2015 (R2020), the operations boundary (or EAB) is the area
Kairos Hermes 2, Units 1 and 2 2-2 Revision 0 Preliminary Safety Analysis Report Site Characteristics
Table 2.1-2: Resident Population Distribution within 5 miles (8 km) of the Site in Morgan County Year Distance Band (miles) 0-0.5 0.5-1 1-2 2-3 3-5 Total 202010 0 0 0 0 381 381 2026 0 0 0 0 386 386 2031 0 0 0 0 390 390 2040 0 0 0 0 398 398 Sources: Reference 9, Reference 10
Kairos Hermes 2, Units 1 and 2 2-6 Revision 0 Preliminary Safety Analysis Report Site Characteristics
Facility, Kairos Power Atlas Fuel Fabrication Facility, TRISO-X Fuel Facility, Clinch River Nuclear Site, Coqui Pharmaceutical, and the regional airport) are currently proposed and not yet under construction.
The PSAR for the proposed Kairos Power Hermes Facility has demonstrated that the off-site radiological impacts at the site during routine operations and severe accidentspostulated events would be within regulatory limits (Reference 33). The Hermes facility would include storage of approximately 21,555 gallons of diesel fuel in an onsite fuel tank for the standby diesel generator. The Hermes facility will have an inventory of 40,000 pounds of low-pressure, molten salt coolant i.e., Li2BeF4 (Flibe). The location and quantities of all chemicals that would be stored at the Kairos Power Hermes Facility have not yet been determined or finalized. The explosion analysis of the Hermes onsite fuel tank is further discussed in Section 2.2.3.1. The hazard due to the release of radioactive material from the Kairos Power Hermes Facility, as a result of normal operations or an unanticipated event, is not expected to affect the safety of the facility due to the low reported doses. Smoke detectors, radiation detectors, and associated control equipment will be installed at various plant locations as necessary to provide the appropriate operation of the systems. Radiation monitoring of the control room environments will be provided by the radiation monitoring system.
The Early Site Permit Application (ESPA), Part 2, Site Safety Analysis Report (SSAR) for the Clinch River Nuclear Site has demonstrated that the off-site radiological impacts from one or more nuclear reactors at the site during routine operations and severe accidents would be within regulatory limits (Reference 9). Furthermore, while the site would be within the Low Population Zone (LPZ) for Clinch River Nuclear Site reactor(s), the site would be outside the Clinch River Nuclear Site Emergency Planning Zone (EPZ)
(Reference 9).
The Coqui Pharmaceutical site is excluded from the discussion in the following sections as there is currently not enough information available for an analysis. However, the radiological effects from the radiopharmaceutical production facility at the Coqui Pharmaceutical site would be within regulatory offsite dose limits for routine operations and accidents. Additionally, the operations are expected to be similar to the SHINE Medical Technologies which received a construction permit from the NRC in 2016 for a radioisotope production facility located in Janesville, Wisconsin. SHINE Medical Technologies demonstrated in its PSAR that releases of onsite chemicals were not a hazard to personnel in the facility control room (Reference 18). As such, chemicals stored onsite at the Coqui Pharmaceutical site would similarly not be expected to have an impact on nearby facilities, including the Hermes 2 facility.
The location and quantities of chemicals that would be stored nearby at the proposed Kairos Power Hermes Facility, the proposed Kairos Power Atlas Fuel Fabrication Facility, the proposed TRISO-X Fuel Facility, the proposed Clinch River Nuclear Site, the proposed Coqui Pharmaceutical Facility, and the proposed regional airport have not yet been determined. The effects of explosions, flammable vapor clouds, and toxic chemicals for onsite chemical storage at these nearby facilities and at the Ultra Safe Nuclear Corporation Pilot Fuel Manufacturing Facility will be reviewed in the operating license application and accounted for in the final design to the extent information regarding hazards from those nearby facilities are available.
The general aviation airport is discussed in Section 2.2.2.3 and is also evaluated on the basis of estimated information below.
The remaining nearby facilities with potential to affect the reactor facility are evaluated below. The potential effects of those nearby facilities in terms of design parameters or physical phenomena were identified considering guidance in Regulatory Guide 1.78, Revision 1 Evaluating the Habitability of a Nuclear Power Plant Control Room During a Postulated Hazardous Chemical Release, Regulatory Guide 1.91, Revision 2, Evaluations of Explosions Postulated to Occur at Nearby Facilities and on
Kairos Hermes 2, Units 1 and 2 2-21 Revision 0 Preliminary Safety Analysis Report Site Characteristics
Nearby Facilities Three facilities near the site were evaluated in the Clinch River Nuclear Site ESPA, Part 2, SSAR (Reference 9). They were the ORNL-Battelle, located approximately 5 miles (8 km) east of the site; Tennessee Valley Authority (TVA) Kingston Fossil Plant, located approximately 7 miles (11.2 km) southwest of the site; and the TVA Bull Run Fossil Plant, located approximately 15 miles (24.1 km) east of the site. The Clinch River Nuclear Site ESPA, Part 2, SSAR used a conservative TNT equivalency method to determine safe distances for the identified potentially explosive materials. All damaging overpressure safe distances were less than the minimum distance from the storage areas to the Clinch River Nuclear Site. With the exception of the TVA Kingston Fossil Plant, the site is farther away from the nearby facilities evaluated than the Clinch River Nuclear Site, and all distances between the nearby facilities and the site are greater than the minimum safe distances reported in the Clinch River Nuclear Site ESPA, Part 2, SSAR.
During operations, the Kairos Power Hermes facility would include storage of approximately 21,555 gallons of diesel fuel in an onsite fuel tank for the standby diesel generator. The 21,555-gallon diesel fuel storage vessel was assumed to contain fuel vapors at the upper UFL. This is conservative because the UFL produces the maximum explosive mass given that it is the vapor, not the liquid fuel, that explodes.
These assumptions are consistent with those used in Chapter 15 of NUREG-1805. Using other conservative assumptions, an explosion could result in an overpressure safe distance of 500 feet (0.09 miles). The expected distance from the Kairos Power Hermes facility diesel tank to the Hermes 2 facility is assumed to be greater than or equal to 0.1 miles. Therefore, until the exact location of diesel fuel transportation and storage locations are determined, a potential explosion involving the Hermes facility fuel storage tank could result in overpressure that exceeds more than 1 psi, and the Hermes 2 facilitys structural designs should account for this. The effects of explosions, fires, flammable vapor clouds, and toxic chemicals from onsite chemical storage at the Kairos Power Hermes facility will be evaluated in the operating license application and accounted for in the final design.
Based on the proposed Oak Ridge General Aviation Airport EA, a fuel farm is proposed to be constructed operating two 10,000-gallon aboveground tanks for aviation fuels (Reference 11). These tanks would be of double-walled construction (or would employ some other means of secondary containment) and would be equipped with appropriate overfill and spill protection devices. Additionally, spill response equipment, such as absorbent booms and pads, would be made readily available. These tanks may also be required to contain vapor control devices depending on the actual monthly throughput of aviation fuels.
An evaluation of the explosive hazard from a jet fuel tank is provided in the SHINE Medical Technologies PSAR (Reference 18). The SHINE Medical Technologies PSAR evaluated tank of jet fuel containing 500,000 pounds or approximately 75,000 gallons. The tank was modeled using TNT equivalency methodologies to determine minimum separation distance. The model determined that the minimum separation distance from a tank containing 500,000 pounds of jet fuel was 0.22 miles. Combined, the two 10,000-gallon fuel tanks suggested in the Oak Ridge Airport EA (Reference 11) at the proposed Oak Ridge Airport would contain less fuel than the single tank modeled in the SHINE Medical Technologies PSAR, indicating that the minimum separation distance of 0.22 miles would be acceptable for the Oak Ridge Airport as well. Because the distance from the site to the Oak Ridge Airport would be greater than 0.22 miles, fuel stored at the airport would not present an explosive hazard with a potential of impacting the site.
Although unlikely, a boiling liquid expanding vapor explosion (BLEVE) could occur to one or both of the 10,000-gallon fuel tanks at the proposed Oak Ridge airport as a result of a high-temperature fire.
Therefore, BLEVE analysis was conducted for a single 10,000-gallon tank of jet fuel (Jet A) and a single
Kairos Hermes 2, Units 1 and 2 2-25 Revision 0 Preliminary Safety Analysis Report Site Characteristics
Precipitation averages about 56 inches annually (Reference 4). Late winter (January-March) is usually the wettest season, with more than about 16 inches, while late summer-early autumn (August-October) is the driest season, with more than 10 inches. Droughts are uncommon in this region of the United States.
Snowfall in the Oak Ridge area, though normally light, usually occurs from November through March.
Severe storms are relatively infrequent as the region is east of maximum tornado activity, south of the most significant snowstorms, and inland from hurricane and tropical storm tracks (Reference 6).
The regional meteorological conditions that are relevant to the design and operating bases for the site are discussed below.
2.3.1.1 Severe Weather Severe weather phenomena may require consideration in the design of safety-related structures, systems, and components. Statistics on severe weather phenomena are obtained from historical data.
Most data are taken from the NCDC Storm Events Database (Reference 7) that covers the 71-year period of 1950-2020, but even longer data periods are used for some phenomena to better capture the occurrence of rare events, such as maximum historical snowpack (see Section 2.3.1.11).
2.3.1.2 Thunderstorms Thunderstorms are common in the Oak Ridge region with a normal range of 34-65 days with thunderstorms based on data collected from 2001-2021 at the Oak Ridge National Laboratory (ORNL)
(Reference 8). The greatest frequency of thunderstorms is during the summer with a range of 18-40 days during May-August. This is characteristic of a diurnal afternoon thunderstorm pattern due to solar heating.
2.3.1.3 Hail In Roane County, severe hail (3/4 inch in diameter or larger) has been reported only 36 times during 1950-2022 (Reference 7). This corresponds to less than one severe hail event per year. During the same period, surrounding counties reported severe hail between 50 (Loudon) and 94 (Knox) times.
2.3.1.4 Lightning The site averages four to eight cloud-to-ground lightning flashes per square kilometer annually based on a 26-year period from 1993-2018 (Reference 9).
A review of cloud-to-ground lightning strike data from a 10-year period from 2011-2019 at the site indicates that 7 of the 10 years had a lightning strike occurring within 500 hundred feet of the site or beside the site (Reference 46). One of these years, 2012, was a year with an exceptionally high number of cloud-to-ground lightning strikes. Eleven lightning strikes occurred within the site boundary with several more strikes occurring within 500 hundred feet of the site (Reference 47).
2.3.1.5 Extreme Winds Windstorms are relatively infrequent but may occur several times a year, usually associated with thunderstorms. Moderate and occasionally strong winds sometimes accompany migrating cyclones and air mass fronts. The strong winds are usually associated with lines of thunderstorms along or ahead of cold fronts and are more probable in the late winter and spring than any other time of the year. Brief, strong gusts of wind due to downdrafts and outflow from individual thunderstorms can occur but are generally limited to the large, intense thunderstorms that develop in the spring and summer.
Estimated extreme winds are based on climatological data from Oak Ridge and Knoxville, Tennessee, (References 5, Reference 2) and hourly observations from ORRs meteorological Tower J and Tower L
Kairos Power Hermes 2, Units 1 and 2 2-49 Revision 0