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BORDER SURVEILLANCE in the 21st century by Barrie Smith Detecting contraband, armaments and illegal immigrants as they cross borders has been likened to looking for that proverbial needle in the haystack. But that is changing, with amazing new technology already in use and even more just be around the corner. . . 8  Silicon Chip siliconchip.com.au A s the gap between the developing and developed countries continues to grow, there are millions of people wanting a better life in the USA, Canada, UK, Australia and Europe. A spokesman for Canada’s Royal Mounted Police claims at any one time, 18 million people are poised to make a covert voyage to one country or another. These poor (in every meaning of the word) people are willing to borrow, beg and shell out huge amounts of currency to get to the land of their hopes. And there are lot of criminals willing to take their hard-won savings. In 2000, 58 illegal Chinese immigrants died in an airtight truck container at the port of Dover, having been transported across the continent, then across the Channel. The driver and a London-based accomplice were sentenced to 14 and 6 years imprisonment respectively. French Customs in 2001 intercepted a 7.5m truck on a Channel ferry packed with rags and fabric – and 24 Indian nationals loaded in Paris and close to asphyxiation. At the UK end of the Channel Tunnel Customs examined a tanker, laden with sand and 35 Indian ‘illegals’ who had been on the road from Belgium for 4-5 hours. Nine more were found sitting on a load of frozen chickens in a freezer truck chilled to -9°C. Although they were wrapped in thermals the solid-sided vehicle had no exit mechanism and no way for them to leave the vehicle in an emergency. Eight Turkish Kurds, including two children, were found dead in Wexford, Ireland having hidden in a metal container they believed was headed The Chinese developed NUCTECH X-ray scanner now operating in Melbourne, Sydney and Brisbane. It can detect a 1.5mm metal wire hidden behind 10cm of steel. to Dover. A body was found in the wheel well of a US Airways jet at San Francisco International Airport. The unidentified man was discovered a few minutes after landing. Solutions US border authorities believe they have an effective stopper for ‘kamikaze smugglers’ — cars packed with illegal immigrants and drugs that zip across the US-Mexican border. Called a Vehicle Stopping System (VSS), the device snares smugglers in high-tech nets; it stops suspects from fleeing by wrapping around the doors of the vehicle. Road spikes were not “a good solution” because the vehicles lost control and anyway, it was believed, smugglers could drive over the spikes by filling their tyres with silicone. Every year, 16 million containers move through America’s 361 ports, while only 4% of them are scanned — a big hole in the nation’s ‘terrorist shield’. The West Coast ports of Los Angeles-Long Beach, Oakland and Seattle currently process 11,000 containers per day. While people smuggling is a serious problem worldwide, the US itself is People smuggling by road is big (illegal) business, particularly in the US and Europe. Here’s a “load” of illegal immigrants attempting to enter the US hidden deep inside a cargo truck. But modern surveillance equipment can penetrate the steel walls of the truck. siliconchip.com.au also on high alert for illegal terrorist material imports — bombs, nuclear devices and so on. As detection techniques forge ahead, a number of approaches are now being either considered or taken up by authorities in their battle against smugglers. Some methods are claimed to offer comprehensive success in discovery of contraband — human and otherwise — while others are only partially successful. From the Air An Israeli company supplied two Hermes-450 aerial drones to monitor the Arizona border patrol and secure a 560km stretch of the US-Mexican border — known to be the most popular corridor for illegal immigrants. The remotely piloted vehicles can fly up to 145km/h, detect movement from 25km away and transmit live pictures day and night. Melbourne X-ray scanner A Chinese-developed X-ray scanner now operates at Swanson Dock in the Port of Melbourne, scanning steel shipping containers for drugs, armaments, explosives and other materials – and people. Measuring 35 x 15 metres, the scanner is driven by a six million electronvolt linear accelerator that projects a narrow vertical beam, able to penetrate 260mm of steel. It can detect a 1.5mm metal wire hidden behind 10cm of steel. However the level of radiation around the scanner is less than that of a standard hospital chest X-ray machine. Broadly, the container scanner is a very large version of the machines used to check luggage at airports. Trucks carrying up to three 6-metre containers are driven into the scanner shed and parked under a rolling gantry carrying the beam projector. Drivers step down into a waiting room insulated against radiation while the February 2005  9 scanner, riding on a set of rails, runs the length of the truck. The gantry travels at 10 metres a minute, scanning a semi-trailer load of three six-metre containers in about 2.5 minutes. A receptor on the far side of the gantry gathers data produced by the X-ray beam and projects a digital image of each container’s contents on to computer screens in a control room where they are analysed by customs examiners. The whole process takes a little more than 10 minutes per truck. The facility handles about 100 containers a day. Analysis of the images on monitoring screens takes another 10 minutes or so; the operator looks for ‘anomalies’, so if something does not fit the description of the cargo supposed to be inside, the container is manually examined in a nearby shed. Illegal drugs are among the most common seizures. Humans are rarely discovered — but sometimes they are found dead, asphyxiated in an airtight container. The Melbourne container scanner is the first of four bought by customs from NUCTECH Company Limited, the Chinese enterprise which is the largest producer of container and vehicle X-ray inspection systems in the world. Similar facilities are being built at Sydney, Brisbane and Fremantle. Texas Rays At checkpoints on Highways 77 and 281 in Texas, mobile truck-mounted X/gamma ray machines, costing half a million US dollars, are reported to scan a truck’s cargo in seconds in the search for ‘illegals’. TV and radio campaigns warn Latin American viewers of the dangers involved in people smuggling, while a bi-lingual campaign informs truck drivers of the penalties involved in smuggling illegal aliens. Neutron Scanner Examples of NUCTECH scans. 10  Silicon Chip To date, industrial X-ray scanners are unable to reliably detect nuclear or fissionable materials transported in cargo containers due to the latter’s mass (some weigh up to 27 tonnes) and the mix of their cargo — food, sports gear, liquids — all of which may provide frustrating shielding. Over the last few decades, several industries have begun to use thermal, or low-energy, neutron imaging as a complementary technique to X-ray imaging for inspecting objects. Neusiliconchip.com.au Livermore Laboratory design for a high energy neutron imaging system, consisting of a powerful neutron source, multi axis staging platform to hold and manipulate an object and an effective imaging detector (CCD). Livermore Laboratory physicist James Hall with imaging scintillator (light source) of neutron scanner. trons are electrically neutral particles similar in mass to a proton and present in the nuclei of all elements — except hydrogen. The drawback to these lowenergy systems is that they are generally limited to inspection of objects only a few centimetres thick. Now Lawrence Livermore National Laboratory (University of California) researchers has demonstrated the power of using high-energy neutrons as a non-destructive inspection tool for evaluating the integrity of thick objects such as nuclear warheads and their components. In non-destructive surveillance Xrays are adequate for inspecting the condition of high-Z (high-atomic-number) materials such as lead, tungsten and uranium. But X-rays are not always effective in revealing cavities, cracks or other defects in low-Z (low-atomicnumber) materials such as plastics, ceramics, lubricants and explosives when these materials are heavily shielded by thick, high-Z parts. High-energy neutron imaging offers unique advantages over conventional X-ray and thermal neutron imaging, particularly for inspecting light low-Z elements that are shielded by high-Z elements. High-energy neutrons have greater penetrating power through high-Z materials and, compared to X-rays, much stronger interaction in low-Z materials, so yielding more detailed images of the latter. siliconchip.com.au This imaging detector consists of a 60cm diameter transparent plastic scintillator (a component that gives off light when a charged particle passes through it), viewed indirectly by a camera with a high-resolution (2048x2048 pixels) CCD. A thin turning mirror made of aluminised glass reflects the brief flashes of light, generated by neutrons interacting in the scintillator, into the CCD camera. The camera has a fast f/1.0 aperture lens to enhance its sensitivity and is cooled with liquid nitrogen gas to -120° C to minimise dark current noise (to which CCDs are prone). Exposures can be as long as 30 minutes per capture. The final Livermore detector would work by firing a neutron beam through a cargo container as it rolls along a conveyor belt between two large, flat arrays of detectors (jokingly called a ‘nuclear car wash’). The high-speed neutrons would split atoms within concealed uranium or plutonium. The atoms would exhibit their presence by emitting their own telltale electromagnetic radiation (gamma rays) and neutrons, which could be sensed by the detector arrays. Scientists want to be able to detect at least one kilogram of plutonium, significantly less than is required to make a bomb — but some terrorists might try to evade security scanners by bringing fissionable materials into the country in small pieces for later assembly. There are some problems ahead: for example the enriched uranium or plutonium may be shielded with lead, (absorbs gamma rays) or with materials rich in hydrogen (water, wax or wood), which absorb neutrons. Another difficulty is how to pick up Hall and co-workers set up the scanner test. February 2005  11 Bales of marijuana (1) hidden behind a false wall (2) in the rear of a truck, with more bales hidden under a load of hay. the signal of bomb materials against the background noise of cosmic rays in the environment. And the neutrons have to be intense enough to detect fissionable materials without being severe enough to harm human stowaways. The Neutron Race There is an Australian research neutron X/gamma ray research venture being piloted by Dr Brian Sowerby, Project Leader and Chief Scientist, with his team at the CSIRO Minerals unit, based at the Lucas Heights, NSW reactor. Is there a race? Possibly, as the unit is discouraging publicity prior to the official launch and images of the scanner cannot be released. The Australian Government has allocated $8.4 million to the Customs Service to develop a contraband scanner that can quickly and accurately detect illegal drugs and explosives. Using the CSIRO approach the aim is to construct a commercial scale scanner and facility in Brisbane, to trial the technology in 2005. Whereas the US Livermore device is known to be slow in operation at this stage of its development, the Australian venture should have speed on its side and be less intrusive commercially – scanning an air-freight container should take less than two minutes. The Australian scanner combines Xray scanning and the neutron method. It is expected to be around a quarter the cost of the Livermore device, so there should be considerable market interest in it. Customs and CSIRO have already 12  Silicon Chip successfully prototyped, tested and patented the device, thanks to the building of a full-scale prototype at Lucas Heights. In tests it scanned standard air cargo containers and correctly identified a wide range of concealed contraband. In a press release from the CSIRO Dr Nick Cutmore, Program Manager at CSIRO Minerals explains that the main advantage of the scanner, over current and potential new scanners, “is its ability to accurately and rapidly detect and predict the composition, shape and density of an object — in real-time on the tarmac.” Conventional X-ray scanners can detect objects based on their density and shape — but not their composition. X-rays and their variations fall down when there is a need to detecting materials like drugs and explosives, plastics and organics. Dr Cutmore believes the scanner is unique in the way it uses gamma rays and neutron analysis to construct an image and the composition of the object being scanned. The CSIRO scanner is able to distinguish varying classes of compounds; organic materials can be detected, even when hidden behind heavyweight objects. One example is that drugs have been detected in tests, even when placed inside concrete blocks. While keeping a tight rein on information on how the scanner actually works, Dr Sowerby has been quoted in an ABC Radio interview as explaining that a combination of commercially available components were used — but that the key component is the detector ray itself. The principle harks back to some years of earlier research in on-line This contraband detection X-ray system has civil libertarians in a real tizz as it is capable of revealing quite intimate body details (as you can see), along with contraband secreted both on and inside the body. One would have to ask if this is any more intrusive of civil liberty than a full body search of a suspect? siliconchip.com.au low doses of radiation to make an image of the freight, via a highly sensitive detector array system. It moves along the whole length of the vehicle and typically takes a few minutes to produce an image. The scanning equipment uses low exposure high-energy X/gamma radiation systems, linked to a detector array sysDr Brian Soweby with an air cargo container tem, which images the standing on the prototype scanner platform. contents of the vehicles analysis instrumentation for the minand/or freight. eral and coal industries. This used The shielded driver’s cab and operaneutron X/gamma ray techniques to tors cabin form an integral part of the measure the value content of minerals, scanning vehicle and are intended to coal ash and other materials. be occupied throughout the examinaTo apply practical experience to the tion, (which takes up to 50 seconds prototype scanner a quantity of guns, for a 12-metre container and truck). grenades and explosives were taken The tightly collimated X/gamma into Lucas Heights to be stowed into radiation beam scans the vehicle and/ actual airline containers for the tests. or freight either as a ‘flying spot’, scanOne can only imagine the security ning down the vehicle and/or freight headache this must have caused the from top to bottom, or as a fan beam. reactor’s security staff! There are questions about the level Airline and sea containers have a of radiation in order to protect the similar maximum width of a little public, scanner operators and truck more than two metres, so the CSIRO drivers. It is understood the radiascanner is believed to be able to ‘look tion level is not high enough to affect into’ both types. Smaller objects are foodstuffs contained within the trucks well within its ‘view’, possibly right and insufficient to affect humans. down to parcel-shaped objects; in this There is no radiological impact on the case, lower energy neutrons would be environment from using the scanner, employed. as it contains no radioactive material. The report concluded that people UK findings who may fly to the UK to claim asylum The British Immigration Service could well be exposed to a higher dose commissioned a report to determine from cosmic radiation than if they whether the use of “mobile X/gamma were subjected to a scan in a vehicle. ray radiation scanners is justified in In a heartbeat the detection of people seeking to circumvent UK immigration controls.” There have also been trials of heartThe rate of clandestine entry by people beat sensors at Dover and Coquelles concealed in vehicles and/or freight at (in France), respective ends of the ferry ports and the Channel Tunnel is Channel Tunnel. stated to be “very high”. This works by placing up to four Current measures in use include carbon dioxide sensors, which give rapid and generally reliable indications of concealed humans and animals. However, certain types of freight emit CO2, which masks detection. Also, some containers prevent examination by CO2 sensors. The Immigration Service plans to deploy X/gamma radiation scanners at UK ports and control zones as a follow up to the CO2 scanners. The X/gamma ray scanners emit siliconchip.com.au brass sensors, connected to a simple touch screen computer, on the frame of a stationary vehicle. The system is capable of detecting a heartbeat (human, animal, bird etc) by measuring minute vibrations in the vehicle structure and matching them against the known sonic pattern of a human heartbeat. Analysis of this passive millimetric wave imaging uses thermal imaging techniques to detect radiation naturally emitted from objects. Although it can only be used for soft-sided vehicles, it works when the vehicle is moving. Eurotunnel currently uses the system at Coquelles while the British are “looking at it.” Coincidentally, the Ford/Volvo car combine has trialled ‘SecureCar’ in a Volvo S80, using an electronic microaccelerometer, a microprocessor and sophisticated software to detect heartbeats anywhere within the vehicle. The latter also contains two additional systems, designed to aid an individual trapped in the trunk: a CO2 sensor scans the trunk for signs of trapped occupants and a touch-sensitive pad inside the trunk can open the lid if it touches any part of a living being. Ion scanner At Montreal (Canada) Dorval airport ion scanners are used by the Mounties to detect the explosives or drugs inside closed containers, such as packages or luggage. Already ion scanners are heavily used by Canadian customs officers. Deep Scans So, next time you use your desktop scanner to capture the surface of a printed A4 page, spare a thought for the scientists working with X/gamma ray technology and the like as they peer into the contents of a 27 tonne container! SC Ford/Volvo has trialled ‘SecureCar’ in a Volvo S80, using an electronic microaccelerometer, a small microprocessor and sophisticated software to detect heartbeats anywhere within the vehicle. February 2005  13