New radiation detectors for US ports leave lawmakers skeptical

Acquisition of next-generation radiation-detection technology that the US Department of Homeland Security says will vastly improve customs agents’ ability to counter the smuggling of weapons-usable nuclear materials in cargo and vehicles has been delayed as Congress weighs allegations that the $1.2 billion system hasn’t been adequately tested and evaluated.

The advanced spectroscopic portal (ASP) system promises to dramatically lower the occurrence of “nuisance” radiation alarms triggered by cargo at US ports, compared with the existing radiation portal monitoring (RPM) systems. According to Vayl Oxford, director of the Domestic Nuclear Detection Office (DNDO) at DHS, between 400 and 500 false alarms occur each day at the Los Angeles–Long Beach port alone, and 200 000 are tripped annually at all US ports of entry. Another 40 000 alarms are set off at US land border crossings each year.

Oxford told the House Committee on Science and Technology that the ASP should bring the number of alarms down to between 20 and 25 per day at Los Angeles. Field tests of the ASP at the New York Container Terminal also indicated a factor of 10 reduction in nuisance alarms that require secondary inspections. The ASP employs gamma and neutron detectors to identify the specific radiation spectrum emitted by the inspected material.

An independent review team commissioned last year by DHS Secretary Michael Chertoff raised questions about the adequacy of the tests the ASP has undergone; that team supported some of the contentions of a more critical Government Accountability Office review of the DNDO’s testing program. The independent review team’s report, delivered to Congress on 20 February, agreed with the GAO that the tests were not designed to assess the range of ASP system performance and said that test results and measures of effectiveness weren’t properly linked to operational outcomes, so it was difficult to develop conclusions from the results.

Biased?

The GAO had accused the DNDO of using “biased test methods that enhanced the test performance of the ASPs.” GAO officials told a House subcommittee last fall that the agency had conducted numerous preliminary runs of almost all the materials and combinations of materials that were used in the formal tests and then allowed its ASP contractors to collect test data and adjust their systems to identify those materials.

Further, according to the GAO, the tests didn’t use sufficient amounts of masking materials that could be used to shield radioactive materials. When that concern was raised, the DNDO declined to modify its test criteria for fear of missing a June 2007 deadline for certification of the technology by Chertoff, the GAO charged.

George Thompson, chair of the independent review team, told the House Committee on Homeland Security on 5 March that while the testing procedures “were not ideal,” the review team “did not find any evidence that the test results were thereby biased or manipulated.” The team’s report proposed that an alternative to the ASP might be to upgrade the software on the hand-held radioisotopic identification devices used to check cargo containers that have triggered an alarm when passing through one of the more than 1000 monitors at US ports. Existing monitors employ polyvinyl toluene plastic scintillator technology which cannot distinguish plutonium, highly enriched uranium, or other threat materials from naturally occurring radioactive materials such as ceramic tile or kitty litter. It can take up to an hour for Customs and Border Protection inspectors to scan an individual container with the hand-held device with the same degree of consistency as the ASP can do in 15 seconds, Oxford said. In some cases today, further analysis must be performed with help from a CBP laboratory, adding hours more delay to commerce.

Most cargo scanned

Since 8 February, CBP has been scanning for nuclear or radiological materials 100% of cargo entering the country from the Mexican border, 98% of cargo arriving at seaports, and 91% entering from Canada, Oxford said.

The GAO had first raised concerns with the testing program in 2006, which prompted Congress early last year to mandate certification of the technology by Chertoff prior to actual procurement of ASP monitors. The DNDO dutifully conducted three test campaigns and field evaluations at eight sites, while Chertoff ordered the independent review of the test procedures and results.

Representative James Langevin (D-RI), chairman of the emerging threats, cybersecurity, and science and technology subcommittee of the House Committee on Homeland Security, said the larger issue that was raised both by the GAO and the independent review is that the DNDO should not be responsible for testing its development programs. “This lack of a rigorous and independent testing program can easily lead to the development and even the deployment of ineffective equipment,” Langevin warned. Both reports are “extremely nuanced and do not seem to give clear, strong indications of whether this project is achieving its stated goals,” he said. While stressing that he didn’t want the ASP program to fail, Langevin said the tests to date “have not unequivocally demonstrated in an operational setting that the ASP represents a significant improvement over current technologies.”

Oxford said he now expects Chertoff’s decision by August. Some 45 systems have already been built by vendors and could be fielded immediately after receiving the go-ahead. Others could be delivered in four to six months. Although $1.2 billion has been authorized for the procurement, Oxford said the DNDO expects to purchase $350 million worth of the ASPs.