Placing radiation monitors in cargo containers at sea and deploying new spectroscopic monitors at ports could help the United States overcome the inherent difficulties in detecting illicit nuclear material in transit, experts and officials said Tuesday at a House of Representatives hearing.
A recent spate of congressional hearings and expert reports has focused new attention on the obstacles to detecting highly enriched uranium, which emits relatively weak radiation and can be effectively shielded with heavy materials such as lead. Critics say portal monitors deployed in recent years at many U.S. ports are not capable of doing their job.
"An abundance of recent evidence suggests that the technology used may not actually meet the needs at hand," Representative Bill Pascrell, D-N.J., said at the joint hearing of the House Homeland Security Committee subcommittees on WMD defense and emergency preparedness.
Difficulties in detecting highly enriched uranium could be mitigated, acting Domestic Nuclear Detection Office head Vayl Oxford said, by resolving a related problem on which critics have also seized: the frequent inability of current detectors to discriminate among radiation sources.
"Recent reports have been published in the media questioning the overall capability of currently deployed detection equipment," Oxford said in a statement delivered to the subcommittees. "Contrary to public perception that detection equipment is not sensitive enough, the actual primary limitation of today's systems is one of discrimination."
"Specifically," he said, "Today's equipment lacks a refined capability to rapidly determine the type of radioactive materials it detects. Operationally, this leads to higher nuisance alarm rates - the number of alarms that must be resolved by further inspection."
Monitor operators, Oxford said, are turning down the sensitivity settings on their equipment, reducing the number of false alarms but also the probability of detecting a nuclear or radiological weapon. Use of new "spectroscopic" technology that is better able to discriminate among various radiation-emitting materials, he said, could allow monitors to operate at higher sensitivities.
To that end, Oxford's office is spearheading an Advanced Spectroscopic Portal program, which has awarded contracts for monitor development to 10 firms. The program plans "late this summer," he said, to test the firms' prototypes against each other at the new Radiological and Nuclear Countermeasures Test and Evaluation Complex, part of the Nevada Test Site. A "limited number of vendors" will then be chosen to begin production, Oxford said.
National Nuclear Security Administration material protection specialist David Huizenga said that "if these tests are successful," the Energy Department's Second Line of Defense program hopes to obtain some of the new portal monitors for use "in secondary inspection locations" at ports abroad. The new portal monitors would be about eight times more expensive than present detectors.
"The potential improvement in sensitivity may or may not be significant," Huizenga said at the hearing. "Until these monitors are completed and tested, it is impossible to know for sure."
Both Huizenga and Oxford also highlighted the potential for using radiography in conjunction with portal detectors to foil attempts at smuggling shielded nuclear material. By adding radiographic detection of very dense objects, officials hope that when shielding prevents them from detecting radiation, they can identify the shielding itself because of its density.
Homeland Security Associates founder Randall Larsen said in an interview Wednesday that such technology driven approaches fundamentally miss the point. He said that given the impossibility of monitoring tens of thousands of miles of U.S. borders, the highest priority should be on securing or detecting materials before they reach the country.
"I think we're still wasting money putting it in seaports," Larsen said. "We're dealing with a thinking enemy. Some people want to put three locks on the front door and leave the back door open."Checks at Sea Could Detect Low-Rate Radiation
Several witnesses at the hearing endorsed the idea of placing monitors in cargo containers when they begin traveling to the United States. They said the approach could lead to better detection of materials - including highly enriched uranium - that emit radiation at a low rate and, as a result, take time to detect.
The chairman of a recent Defense Science Board task force on detection, Richard Wagner, called such monitoring "a crucially important theme to pursue."
"More attention should be devoted to developing methods of detection at sea," Wagner said at the hearing.
The proposal is one of "several interesting R&D programs exploring new techniques to locate radiological and fissile materials," American Association for the Advancement of Science security technology specialist Benn Tannenbaum testified.
"These detectors take advantage of the 10-day or longer transit time to locate HEU," Tannenbaum said. "This has the additional feature of allowing the interception of dangerous materials before they enter a U.S. port."
Larsen on Wednesday questioned the appropriateness of such plans, citing the large volume of sea commerce bound for the United States - "You know how many ships there are that come in, that cross those 95,000 miles of shoreline?" - and what he called the low likelihood that a nuclear or radiological attacker would choose to attack via shipping container.
"I'd bring it in a cigar boat," he said, adding that only "a very cooperative terrorist" would transport a weapon through a monitored port.
Larsen said spending would be better directed toward securing materials where they lie and that, if more effective detectors are developed, they should first be deployed abroad in hopes of intercepting smuggled materials before they reach the United States.GAO Points to Poor Coordination
In a summary of recent Government Accountability Office reports on nuclear detection, office Natural Resources and Environment Director Gene Aloise told the subcommittees that a long-standing "lack of effective planning and coordination among" the Homeland Security, Defense, State and Energy departments in developing and deploying detectors "has improved" since the recent issuance of a government-wide plan on the subject.
Still, coordination problems remain. Among a host of examples, Aloise said the State Department has installed "less sophisticated" monitors in foreign countries than have the Energy and Defense departments; that Homeland Security was not sharing the data its monitors generated with most Energy Department laboratories; and that various federal agencies have tested portal monitors without sharing their results with each other.
Aloise added that improper use of monitors both in the United States and elsewhere has hindered effectiveness. Operators of Homeland Security portals in the United States, he said, have allowed vehicles to pass through the monitors at high speeds, turned down detection sensitivity and failed to deploy enough handheld monitors.
Turning to efforts abroad, he said half the portal monitors the United States gave one former Soviet country "were never installed or were not operational," that Bulgaria deployed a U.S.-provided portal "on an unused road that was not expected to be completed for 1 1/2 years" and that State Department radiation detection vans are ineffective in cold weather.