The White House has convened an interagency policy committee to address the nation’s shortage of Helium-3 (He-3) gas used in a variety of applications, including neutron detector tubes that are part of radiation portal monitors (RPM), and decided in September that no new He-3 will be given for RPM production for now, a Department of Homeland Security (DHS) official tells Congress.
The shortage of He-3 is “severe,” Dr. William Hagan, acting deputy director for the Domestic Nuclear Detection Office (DNDO), tells the House Science Subcommittee on Investigations and Oversight. Demand will “outstrip supply by a factor of 10,” he said.
He-3, which is a non-radioactive gas given off as a byproduct of tritium decay–tritium being a key component in nuclear weapons–is required to produce currently deployed RPMs and the next-generation systems, called Advanced Spectroscopic Portals (ASPs). The gas is also a critical component in medical imaging systems, the oil and gas industry and high- energy research.
DNDO for several years has been funding research into alternatives to He-3 but once it settles on one, it could take another one to two years to test and evaluate to ensure that it works in RPMs, Hagan says. Some options include separating He-3 found in natural gas wells or acquiring it from other countries, he adds.
Alternatives Being Explored
“Most likely” an alternative to He-3 will have to be found, Hagan says.
DHS has identified four technologies as potential alternative neutron detectors. These are Boron Trifluoride-filled proportional counters, Boron-lined proportional counters, Lithium-loaded glass fibers, and coated non-scintillating plastic fibers, a DHS tells TR2 in a written response to an email. These still need to be developed and explored, DHS says. To accomplish this, DHS plans to host a competition for “vendors to present solutions that could by applied to systems that require neutron detection.”
But the shortage of He-3 is making it difficult to do a cost-benefit analysis between the ASP and the current generation of RPMs, Hagan says. That cost benefit analysis is one of the key data points that will be factored into whether DHS decides to move forward with full-rate production of ASPs, whether the systems are used in both primary and secondary screening of containers entering the U.S. or possibly just secondary applications.
More Field Testing Needed
Before a production decision is made, the ASP program also has to go through a third round of Field Validation Testing with Customs and Border Protection (CBP), which is the end user of the system, followed by operational test and evaluation, which will be carried out by independent test branch of the DHS Science and Technology Directorate.
A third round of field tests is needed after the second round in July found continued problems with one of the systems in development. Those problems include alerting for special nuclear materials when in fact none were in the cargo being inspected and not alerting the operator when a system shut down, thereby causing a number of cargo containers to pass through potentially unscreened. In this case, an existing RPM was also used as a backup for the ASP, preventing the release of unscreened cargo into the country.
The system shut down is considered a “critical failure,” by CBP.
Another problem in the July tests was that the ASP did not reduce secondary referrals by 80 percent, which is one of the criteria DHS has established for the system to achieve “a significant increase in operational effectiveness,” Gene Aloise, director of Natural Resources and Environment at the Government Accountability Office, says in his prepared remarks at the hearing. Instead, the system was able to reduce referrals to secondary inspection by about 69 percent, he says.
Hagan says that DNDO and the contractor, in this case Raytheon [RTN], have found a fix for the false alerting and the system shut down problems. He says the system shut down was only on one system and that the alert message to the operator was confusing. That message on the operator’s console has will be simplified, he adds.
Regarding the false positives, Hagan says a replay tool was used to test the fix and has shown that the vast majority of the problems have been fixed. The replay tool was verified by Johns Hopkins Applied Physics Laboratory but Aloise says that it would be better to have a standards body such as ANSI validate the tool.
To fix the problem of alerting for non-existent nuclear materials, Aloise says that DNDO is reducing the sensitivity of the ASP.
“While this may address the issue of false positive alarms, it will also diminish the ASP capability of detecting a key high-risk nuclear material,” Aloise says. Later, he adds, “By reducing the sensitivity to these materials and not retesting the modified ASPs against actual nuclear materials, it is uncertain exactly what improvement in detecting certain nuclear materials these costly portal monitors are providing.”
Todd Owen, CBP’s executive director for Cargo and Conveyance Security, says his agency believes that DNDO has made the proper fixes to the ASP system and is ready to begin the next round of field validation tests during the first quarter of 2010.
In addition to Raytheon, Thermo Fisher Scientific [TMO] is also developing an ASP system for DNDO. However, Thermo Fisher has not advanced to the field testing phase due to continue technical issues that are being sorted out.
Based on program results so far, Rep. Brad Miller (D-N.C.), chairman of the House panel, says its “hard to see why the ASP should be more than a secondary screening system.”
Current generation RPMs alert for potential radiation threats but can’t identify the material. ASP systems are supposed to be able to alert for, and identify, the radiological material, allowing CBP to reduce the numbers of containers that are both sent for secondary screening and in some cases, have to be physically searched.
CBP says that the current RPMs do not impeded the flow of commerce. CBP currently has about 1,400 RPMs deployed at the nation’s land and seaports of entry.
So far $230 million has been spent by DNDO on the ASP program. The total program cost estimate is currently at $2 billion, including production.
If the next round of field validation testing goes well, DHS’ Science and Technology (S&T) branch will still perform its own independent tests. And before any production decision is made, DHS will also evaluate a cost-benefit analysis and an Analysis of Alternatives. Then the program would be reviewed by the DHS Acquisition Review Board and finally the Secretary of Homeland Security must certify the program per a Congressional mandate.
Once ASP operational testing is completed with S&T, DHS and CBP will utilize the cost-benefit analysis to evaluate deployment options for the existing units, DHS says.