The Omega West Reactor was an experimental nuclear reactor

Nuclear reactor

A nuclear reactor is a device to initiate and control a sustained nuclear chain reaction. Most commonly they are used for generating electricity and for the propulsion of ships. Usually heat from nuclear fission is passed to a working fluid , which runs through turbines that power either ship's...

 located at Los Alamos National Laboratory

Los Alamos National Laboratory

Los Alamos National Laboratory is a United States Department of Energy national laboratory, managed and operated by Los Alamos National Security , located in Los Alamos, New Mexico...

 in Los Alamos

Los Alamos, New Mexico

Los Alamos is a townsite and census-designated place in Los Alamos County, New Mexico, United States, built upon four mesas of the Pajarito Plateau and the adjoining White Rock Canyon. The population of the CDP was 12,019 at the 2010 Census. The townsite or "the hill" is one part of town while...

 NM. OMR was completed in 1956 and primarily used for scientific scale nuclear research until it was fully decommissioned

Nuclear decommissioning

Nuclear decommissioning is the dismantling of a nuclear power plant and decontamination of the site to a state no longer requiring protection from radiation for the general public...

 in 1994. It operated 24 hours a day, five days a week until 1972, when it went to eight hours a day, five days a week operation. The original purpose of the reactor was to collect nuclear material properties in support of the United States

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 nuclear weapons program. Other uses included production of useful medical isotopes

Nuclear medicine

In nuclear medicine procedures, elemental radionuclides are combined with other elements to form chemical compounds, or else combined with existing pharmaceutical compounds, to form radiopharmaceuticals. These radiopharmaceuticals, once administered to the patient, can localize to specific organs...

. The reactor was capable of producing an external beam of neutrons via beam tubes which extended through the reactor shielding. These were provided for external neutron beam experiments including: neutron radiography

Industrial radiography

Industrial Radiography is the use of ionizing radiation to view objects in a way that cannot be seen otherwise. It is not to be confused with the use of ionizing radiation to change or modify objects; radiography's purpose is strictly viewing. Industrial radiography has grown out of engineering,...

, neutron capture

Neutron capture

Neutron capture is a kind of nuclear reaction in which an atomic nucleus collides with one or more neutrons and they merge to form a heavier nucleus. Since neutrons have no electric charge they can enter a nucleus more easily than positively charged protons, which are repelled...

 studies, gamma ray

Gamma ray

Gamma radiation, also known as gamma rays or hyphenated as gamma-rays and denoted as γ, is electromagnetic radiation of high frequency . Gamma rays are usually naturally produced on Earth by decay of high energy states in atomic nuclei...

 studies, neutron cross section measurements and neutron activation

Neutron activation

Neutron activation is the process in which neutron radiation induces radioactivity in materials, and occurs when atomic nuclei capture free neutrons, becoming heavier and entering excited states. The excited nucleus often decays immediately by emitting particles such as neutrons, protons, or alpha...

 studies.

Core design

The core consisted of an aluminum grid with 54 vertical channels arranged in 6 rows by 9 channels wide. The channels could be used for fuel rods, experiments and additional uses. An additional 8 channels were used for control rods. The core was contained in a cylindrical stainless steel

Stainless steel

In metallurgy, stainless steel, also known as inox steel or inox from French "inoxydable", is defined as a steel alloy with a minimum of 10.5 or 11% chromium content by mass....

 tank 2.4 meters in diameter and 7.3 meters tall. The core was surrounded by a heavy concrete

Concrete

Concrete is a composite construction material, composed of cement and other cementitious materials such as fly ash and slag cement, aggregate , water and chemical admixtures.The word concrete comes from the Latin word...

 shield which also served as a secondary containment vessel. One of the configurations of the reactor had a 2.5 inches (63.5 mm) lead

Lead

Lead is a main-group element in the carbon group with the symbol Pb and atomic number 82. Lead is a soft, malleable poor metal. It is also counted as one of the heavy metals. Metallic lead has a bluish-white color after being freshly cut, but it soon tarnishes to a dull grayish color when exposed...

 gamma ray shield installed in the first row and 4 inches (101.6 mm) beryllium

Beryllium

Beryllium is the chemical element with the symbol Be and atomic number 4. It is a divalent element which occurs naturally only in combination with other elements in minerals. Notable gemstones which contain beryllium include beryl and chrysoberyl...

 blocks installed in row 6. This left rows 2 through 5 for installation of fuel and experimental usage. A typical core loading consisted of 33 fuel elements, each containing 236 grams of 93% enriched Uranium

Enriched uranium

Enriched uranium is a kind of uranium in which the percent composition of uranium-235 has been increased through the process of isotope separation. Natural uranium is 99.284% 238U isotope, with 235U only constituting about 0.711% of its weight...

 (when new).

Cooling and moderation

Moderation

Moderation is the process of eliminating or lessening extremes. It is used to ensure normality throughout the medium on which it is being conducted...

 was provided by light water which transferred heat

Heat

In physics and thermodynamics, heat is energy transferred from one body, region, or thermodynamic system to another due to thermal contact or thermal radiation when the systems are at different temperatures. It is often described as one of the fundamental processes of energy transfer between...

 out of the core to the air via cooling towers. The reactor

Reactor

Reactor can mean:* Bioreactor, any device or system that supports a biologically active environment.* Chemical reactor, a device for containing and controlling a chemical reaction* Nuclear reactor, a device for containing and controlling a nuclear reaction...

 could be operated at low power

Electric power

Electric power is the rate at which electric energy is transferred by an electric circuit. The SI unit of power is the watt.-Circuits:Electric power, like mechanical power, is represented by the letter P in electrical equations...

 in natural convection

Natural convection

Natural convection is a mechanism, or type of heat transport, in which the fluid motion is not generated by any external source but only by density differences in the fluid occurring due to temperature gradients. In natural convection, fluid surrounding a heat source receives heat, becomes less...

 mode. At full power the flowrate through the core was 13,250 liters/minute.

Shutdown

The reactor operated successfully until 1992 when an unplanned power spike caused an automatic shutdown. During the shut down an investigation revealed a tritium contaminated cooling water leak at which time the department of energy had the fuel rods removed and placed the reactor in permanent safe shut down mode and scheduled for decontamination and decommissioning. The OMR was fully decommissioned in 1994 and demolished in 2003. The demo project was completed under budget and ahead of schedule.

Specifications

The reactor had a following specification:

• Reactor Vessal - Tank type
• Core Design - 54 fuel rods (maximum)
• Fuel - Highly Enriched Uranium up to 93%
• Coolant - Light Water
• Moderator - Light Water
• Control Rods - 8ea. Borated Stainless Steel
• Maximum power level - 8 megawatts thermal.