Continuity Research Facility Bravo

Overview

Continuity Research Facility Bravo (CRF-B) is constructed within a repurposed former hard-rock mine on the Colorado Front Range. Its working levels lie beneath 140 to 190 meters of crystalline rock. The facility serves two functions: it is the Department's primary archive for research data, model records and preserved collections, and it will host a compute hall that operates independently of Facility Alpha.

Underground siting provides stable temperatures, physical protection and separation from surface weather, wildfire and most forms of accidental damage. It also brings obligations that surface facilities do not have, including ground control, ventilation, radon management, mine water treatment and underground fire and egress safety. The design choices described below follow from both.

Rehabilitation of the mine workings, including ground support and drainage restoration, began in 2025 under an interagency preservation pilot during the ITFCC period. The site transferred to the Department in February 2026. Archive Level 1 was commissioned in June 2026 and has been operated since then under the Long-Duration Information Preservation Program (LDIPP). On 1 September 2026 the Continuity Infrastructure Initiative was expanded to include Facility Bravo, bringing the compute hall fit-out and the site's remaining construction under the same program that delivered Facility Alpha.

Research focus

Primary archive

Archive Level 1 holds the Department's authoritative preservation copies: ICSM release packages and production run records, NCRP reference datasets, published reports and their underlying data, and administrative records designated for permanent retention. Each collection is held on at least two media types. Fixity (checksum) verification runs continuously on the tape tier, and a scheduled sample of optical and microfilm holdings is inspected each quarter. Media choices follow the assessment in DSC-TR-2026-005.

The Neural Data Preservation Framework, released for comment as DSC-TR-2026-011, identifies Facility Bravo as the primary preservation site for neural datasets that meet its packaging and provenance requirements. Under the draft framework, neural data would be held in Bravo’s access-controlled enclave, with a second copy at Facility Charlie.

Hardened computation research

The compute hall, when complete, will run three classes of work: a continuously maintained replica of the ICSM production environment, so that the model can be executed if Facility Alpha is unavailable; large-scale integrity verification of the archive; and NCRP data processing that benefits from co-location with the archive. CIA-DSC will also use the hall to study how computing systems behave over long periods in a stable underground environment, including component failure rates, corrosion and the energy cost of heat rejection to rock. Requirements for the hall are derived in DSC-TR-2026-008.

Technical capabilities

Archive environment

Archive Level 1 is held at 15 °C ±1 °C and 35 percent relative humidity. Surrounding rock at the working levels holds a near-constant temperature close to that set point, so the conditioning plant mostly removes moisture and the small heat load from tape libraries and lighting. Capacity is approximately 120 PB on tape, plus separate vaults for archival optical discs and microfilm. Microfilm cabinets are sealed, and the vault is fitted with acid-gas and particulate filtration.

Heat rejection

The compute hall uses geothermal-assisted heat rejection. A closed-loop ground heat exchanger, drilled into the rock mass away from the archive, absorbs part of the heat load. The rest is carried to surface dry coolers. Instrumented boreholes monitor rock temperature around the loop, and its share of the load is limited so that the rock near the archive does not warm measurably. When the hall is complete, its design-basis PUE will be 1.2.

Power and resilience

The site is served by two independent utility feeds from separate substations. On-site generation at the surface is sized to carry the full site load, including the completed compute hall, ventilation and hoisting, for 72 hours without resupply. Fuel is stored only at the surface. Generators are arranged N+1, and the archive is on separate uninterruptible power supplies and switchgear so that faults in the compute hall cannot propagate to it.

Underground safety and environmental compliance

Underground operations follow applicable federal and state mine safety and occupational health requirements. The working levels are reached by a vehicle portal adit, and a vertical shaft with a personnel hoist provides a second means of egress. Ground conditions are monitored with extensometers and convergence stations and maintained with rock bolting and shotcrete. Ventilation is supplied through dedicated intake and exhaust airways. Radon, carbon monoxide and oxygen are monitored continuously, and pre-stocked refuge stations are located on each working level. The archive vaults use inert-gas fire suppression and the compute hall uses water mist. Mine water is collected, treated at the surface and discharged under the site’s environmental permits.

Specifications