Valar Watch · Fact safe-021

Fact safe-021

newanalysisconfirmed Earthquakes, floods, fire: DOE's review names only a fault 150 km away; state maps show a fault zone about 15 km away

2026-09-29 · safe-021 · Valar Atomics, U.S. Department of Energy, Utah Geological Survey

The NSDA's natural-hazard values are 'preliminary', based on 'regional seismicity and generic site conditions', with final values to follow site-specific studies: peak ground acceleration 0.2 g for its most important equipment, 130 mph design wind, 200 mph tornado wind, -20 to 115 F. DOE's categorical exclusion says no active faults, landslides or geologic hazards exist at or next to the site per Utah Geological Survey mapping, calls the region moderate seismic hazard, and names only the Wasatch Fault Zone, about 150 km (95 miles) northwest. A query of the Utah Geological Survey's Quaternary fault layer on 29 September 2026, from a point on Coal Haul Road beside the lab (39.244 N, 111.094 W; accurate to about 2 km), found no mapped fault closer than about 14.8 km (9 miles); six strands of the Joes Valley fault zone lie within 20 km: the nearest (last movement mapped as less than 2.6 million years ago) at about 14.8 km, and strands mapped as having moved within the last 15,000 years at about 15 to 19 km, all with slip rates under 0.2 mm a year. Allowing for the reference point's uncertainty, the nearest strand is roughly 13 to 17 km from the reactor. Flooding: the NSDA places the site on a mesa about 100 ft above the surrounding terrain, and the CX about 100 ft above Cottonwood Creek and outside FEMA-mapped flood areas; the CX notes the Adobe Wash Regulating Reservoir about 0.4 km southwest, which drains through a separate wash that does not cross the site's drainage. Fire and aircraft: the NSDA screens out wildland and industrial fire on a '10-mile separation distance' and aircraft on 'no nearby airports'; the CX describes the site as pinyon-juniper woodland and 'typical undisturbed rangeland', and the state's airport layer shows Huntington Municipal Airport about 20 km away. Water: the CX puts consumption under 1,000 gallons a day for domestic use, with no process-water discharge; the reactor is cooled by helium, not water. Whether the site-specific seismic study was done, and its result, is in the DSA, which was not found in public records. Our check of the earthquake value: the USGS design-maps service (ASCE 7-22, 29 September 2026) gives a maximum considered peak ground acceleration of about 0.21 g for the site on soft rock (site class BC), 0.23 g for class C and 0.26 g for class D; the paper's 0.2 g is close to the rock value, and the paper gives no soil class.

In plain termsDOE's environmental review mentions only a fault 95 miles away. The state's own fault map shows a closer one, the Joes Valley fault zone, about 9 to 12 miles away, with parts that have moved in the geologically recent past, though slowly. That does not make the site unsafe; it means the public review left out the nearest known earthquake source, and the company's earthquake numbers were preliminary. The flood reasoning (a mesa well above the creek) is consistent across documents. The company's fire screen rests on a '10-mile separation distance' from fire sources, while DOE's own description puts the site in pinyon-juniper woodland. Our check of the paper's earthquake value: the 0.2 g is close to the USGS design value for the site on soft rock (about 0.21 g), though softer soil would raise it to about 0.23-0.26 g and the paper gives no soil class.

Ward250 Nuclear Safety Design Agreement, No. 100403, Rev 02 (status: Draft; issued for Public Release) (Valar Atomics, 2025-10) primary company “Preliminary seismic parameters based on regional seismicity and generic site conditions”
NEPA Determination DOE-ID-26-005: Valar Ward250 Research Reactor (categorical exclusion B5.26) (U.S. Department of Energy, Office of Nuclear Energy (Idaho), 2026-04-22) primary government “The Wasatch Fault Zone is located approximately 150 km (95 miles) northwest of the site.”
Utah Quaternary Faults (Utah Geological Survey, Hazards/quaternary_faults MapServer, distance queries) (Utah Geological Survey) primary government
Ward250 Nuclear Safety Design Agreement, No. 100403, Rev 02 (status: Draft; issued for Public Release) (Valar Atomics, 2025-10) primary company “screened based on 10-mile separation distance and natural barriers”
AirportLocations (Utah Geospatial Resource Center, FAA airport points, distance query) (Utah Geospatial Resource Center) primary government
NEPA Determination DOE-ID-26-005: Valar Ward250 Research Reactor (categorical exclusion B5.26) (U.S. Department of Energy, Office of Nuclear Energy (Idaho), 2026-04-22) primary government “Elevated position approximately 100 feet above Cottonwood Creek eliminates flood risk.”
Ward250 Nuclear Safety Design Agreement, No. 100403, Rev 02 (status: Draft; issued for Public Release) (Valar Atomics, 2025-10) primary company “approximately 100 feet above the surrounding terrain”
U.S. Seismic Design Maps web service, ASCE 7-22, Risk Category IV, site class BC, at the USREL site (39.2395 N, 111.0866 W) (U.S. Geological Survey) primary government “"pgam": 0.21”

verified 2026-09-29: Re-ran the UGS Quaternary-fault query on 2026-09-29 (20 km radius from 39.244 N, 111.094 W): nearest Joes Valley strand 14.8 km, strands younger than 15,000 years at 15.1-19.0 km, slip under 0.2 mm/yr; distances corrected from '12.5-15 km'. Airport layer re-read (Huntington Municipal about 20 km). Fixed: only the CX mentions Cottonwood Creek and FEMA; the NSDA says 'above the surrounding terrain'. Correction 2026-09-29 (calculation audit): detail and plain add our check of the seismic, low-temperature and wind values. Correction 2026-09-30 (source objectivity review): reworded the plain-language text; reworded the detail; now also cites U.S. Geological Survey; The State's map layer cited here (Utah Geospatial Resource Center, hosted on ArcGIS Online) was queried on 29 September 2026; that server's robots rules do not allow a saved copy, so none is kept and the figures rest on the cited layer as queried that day.

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