HOMELAND security experts are evaluating
a wide range of possible threats from terrorists. One of the more
troubling scenarios is a small and crude nuclear device transported
in and detonated from a boat located near a naval military base
or a civilian shipping terminal. Thanks to a Livermore design,
buoys outfitted with commercially available radiation detectors
could soon play an important role by warning of the presence of
nuclear materials in marine environments.
Two such buoys guard the marine entrance to the U.S. Navy’s
submarine base at Kings Bay, Georgia. Housing radiation detectors,
telemetry systems, and solar- and wind-powered generators, the
buoys are proving themselves in a demonstration project sponsored
by the Defense Threat Reduction Agency (DTRA).
At Kings Bay, Georgia, two buoys containing
radiation detectors guard the marine entrance as part of
a demonstration project sponsored by the Defense Threat
New Security Uses
for Existing Technology
a federal agency charged with safeguarding the nation from weapons
of mass destruction, has formed a partnership with the
National Nuclear Security Administration (NNSA) to evaluate commercially
available technologies that could be deployed quickly to defend
against threats posed by weapons of mass destruction. One of the
agencies’ top priorities is preventing nuclear weapons, including
crude devices and so-called dirty bombs, from being delivered by
unconventional means, such as by car or boat.
nuclear engineer John Valentine says that the goal is to improve
the Department of Defense’s ability to detect,
identify, respond to, and prevent unconventional nuclear attacks. “We
want to determine how we can protect military bases by using commercial
technology to detect nuclear materials that might be delivered
by truck or boat.” He says that if the new detection devices
are successful, they could also be installed in civilian areas
such as busy ports.
who led the engineering tasks for the buoy demonstration project,
notes that Livermore experts have also taken part in nuclear
detection system demonstrations at Kirtland Air Force Base in New
Mexico, Camp Lejeune Marine Base in North Carolina, and Fort Leonard
Wood Army Base in Missouri. All three projects involved demonstrating
radiological “sentries” for monitoring large areas
of land. The sentries, including stationary radiological sensors
placed along roads and units mounted inside vehicles, were designed
to identify and track any vehicle that posed a threat.
about 48 kilometers north of Jacksonville, Florida, Kings Bay is
surrounded by islands, and the area has heavy recreational
traffic. For the demonstration, the national laboratories were
asked to use equipment capable of operating in marine environments
and detecting nuclear materials that might be used by terrorists,
demonstrate their reliability and performance, and incorporate
them with a base’s existing security system. The Livermore
buoys are one of three water-based detector platforms under evaluation
at Kings Bay. Two other designs, by Sandia and Los Alamos national
laboratories, are floating platforms.
says that buoys offer several advantages for marine environments.
They are built to withstand the rigors of salt water and high winds,
they are unremarkable, and they can be situated in any body of
water that is at least 10 meters deep. However, buoys also offer
challenges such as furnishing adequate power to the detectors and
other instruments, transmitting data to the base, and calibrating
their detectors when the background radiation levels are not well
Two commercial stainless-steel buoys,
one painted red and the other green, were manufactured
in Houston and delivered to Lawrence Livermore on Thanksgiving
weekend 2002 for modifications. The buoy towers, which
were attached in Kings Bay, are visible just behind the
The team installed a stainless-steel
enclosure inside each buoy tower for holding several kinds
of radiation detectors and other sensors.
Buoy Design and Fabrication
Kings Bay project involved Livermore people from the Engineering;
Nonproliferation, Arms Control and International Security (NAI);
Chemistry and Materials Science; and Computation directorates.
The biggest challenge for the team, led by NAI’s Jim Morgan,
was to get from design to deployment in just four months. Designs
for the two buoys (consisting of a base and tower) were finalized
in October 2002. Two commercial stainless-steel buoys, one painted
red and the other green, were manufactured in Houston and delivered
by truck to Lawrence Livermore on Thanksgiving weekend for modifications.
The buoys weigh 6,800 kilograms each and measure 2.4 meters in
diameter by about 8 meters tall. About half of the base floats
team designed and then had constructed a pair of leak proof, stainless-steel
enclosures for insertion inside each
Within each enclosure is a shock-mounted internal frame on which
several kinds of neutron and gamma-ray detectors are mounted so
that the team can compare their effectiveness. “Although
we are using some recently developed detectors, some of the detector
technology in the buoys is about 50 years old,” says Valentine. “Thus,
in many respects, this project is best described as a novel implementation
of existing technology. No one, to our knowledge, had ever put
radiation detectors on buoys before.”
monitor the pitch, yaw, and roll of the buoy. Monitoring the buoy’s
orientation in three dimensions is important to recognizing a threat
from the right craft. Other instruments record
internal frame temperature (detectors are affected by heat), salinity
of the water, and the status of an array of 12-volt photovoltaic
batteries. The 16 batteries are powered by four, 55-watt solar
panels and a small wind turbine.
Each buoy has a radio for transmitting data back to a receiver
on base, where the data are carried by optical fiber to security
headquarters. In addition, two video cameras are trained on the
buoys from a pier about a kilometer away.
buoys and their associated equipment arrived at Kings Bay on December
27, 2002. The two enclosures with all the equipment were
mounted inside the towers early in January, and then the towers
were mounted on the buoy bases. Following final assembly and testing,
the buoys were attached to their anchors (5,600-kilogram chunks
of concrete) and deployed on January 7, 2003, from a barge-mounted
crane. The green buoy is in 15-meter-deep water, and the red buoy
is in 10 meters of water. They are separated by 274 meters.
each buoy is a set of 16 photovoltaic batteries charged by
four solar panels and a wind turbine. On shore, two directional
antennas receive data from the buoys, and two video cameras
are trained on them.
the Buoys to the Test
The buoys are located about 2,200 meters outside a gate that opens
and closes to let submarines in and out of the Kings Bay base.
The Livermore team was required to obtain approvals from the Navy
and Coast Guard for the exact location to place the buoys, which
were officially numbered and entered on nautical charts.
“The buoys are serving as a test bed that allows us to evaluate
the capabilities of the different detectors,” says Valentine.
The team is also tracking the performance of the onboard computer,
telemetry, power systems, and sensors.
January 16, 2003, a demonstration of all the prototype marine detector
platforms was held before about 80 guests, including representatives
from Congress, the Department of Defense, NNSA, DTRA, the Department
of Homeland Security, and the Department of Justice. A pontoon
boat carrying a variety of radionuclides passed by the detector
platforms. In response, both buoys sent messages to base security
that the background radiation limit had been exceeded. Valentine
says that a guard in the base security building could see two icons
(representing the two buoys) on a computer console turning from
green to flashing red. Catherine Montie, DTRA program manager,
gave the demonstration an “A+,” and Valentine anticipates
that the buoys will remain deployed while funding continues.
Following final assembly and testing,
the buoys were deployed January 7, 2003, from a barge-mounted
“The demonstration was an important first step,” says
Valentine. He is leading a follow-on effort that involves upgrading
software and hardware, establishing a temporary remote (from Livermore)
monitoring capability, characterizing the marine background radiation
around Kings Bay, and determining better the capabilities of the
know a lot about terrestrial background radiation but much less
about radiation levels on the water. We know that radiation levels
can vary considerably during the day and night on land. That may
also be true at sea. At Kings Bay, the water is brackish. During
high tide, it is mostly salt water, and during low tide, it is
mostly fresh water. The differences in salinity may cause changes
in background radiation.”
says the buoys could be integrated into the base security system
in the near future. Then
when a threat appears, a security
guard will be able to click on a red flashing computer icon, see
a real-time video image of the area around the buoy, and learn
of the probable radioisotopes carried by the suspicious vessel.
also says that similar buoys could be put to good use in busy harbors.
Proposals have already been submitted to deploy
buoys with radiation detectors in the harbor at Oakland, California.
Buoys, a common marine sight, may prove to be the next level of
protection in the war on terrorism.
Key Words: Defense Threat Reduction Agency (DTRA); homeland security;
radiation detector; U.S. Navy submarine base at Kings Bay, Georgia.
For further information contact John Valentine (925) 424-3261
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