Hazardous waste generated by Mexican manufacturing plants near the U.S.-Mexico border that use raw materials from the United States must be disposed of in the United States under provisions of the North America Free Trade Agreement. But the EPA has no means of tracking those shipments, said Deborah Kopsick, an environmental scientist with EPA's Office of Air and Radiation.
If RFID proves viable, Kopsick said, it would provide the EPA "with a better handle on waste shipments [including] where it enters the United States and when it gets to a disposal facility." She said the EPA would like to test RFID tags and readers from as many as 10 vendors at the Santa Teresa, N.M., border crossing early in 2008 to determine whether the technology can meet the agency's requirements, which are challenging for RFID vendors.
For example, Kopsick said EPA wants to determine if RFID readers can translate tags affixed to metal drums inside trucks as they are moving through a stationary portal at the Santa Teresa Port of Entry, which is operated by U.S. Customs and Border Protection. She ruled out the use of hand-held readers because an agent then would need to board a truck, "and we do not want to interfere with the flow of commerce," she said.
The EPA solicitation established tough parameters for the test, including a 100 percent read rate of RFID tags through metal, liquid, solids and viscous materials from a range of five to 10 feet. Kopsick admitted that meeting a 100 percent target could be a "difficult problem," especially for metal containers containing liquids. Metal repels radio signals and liquids absorb them, making it difficult for RFID readers to receive a signal back. But, she added, "this is something the industry has been working on for a long time, and we believe they can come up with a good system" that comes close to meeting the agency's requirements.
Kopsick said EPA hasn't taken a position on whether to use using active or passive RFID tags in the test. "That's up to the vendors," she said. Active tags are battery powered and have a longer range than passive, which have no battery power and respond to a signal beamed from a reader. Passive tags, however, are cheaper than active ones.
The Government Accountability Office estimated in a 2006 report (GAO-06-366R) that active, reusable tags used to track container shipments to U.S. forces in the Mideast cost about $100 each, and passive tags cost about 30 cents for high-volume orders.
During the test, Kopsick said the data will be read locally in Santa Teresa and at a disposal facility the agency has yet to select. The readers will provide information about when the waste crossed the border and when it reached the disposal facility.
Teresa Harten, director of the EPA Environmental Technology Verification Program, emphasized that, at the moment, EPA is only testing the use of RFID to track hazardous waste, "and at this point we are not looking at any kind of regulations" to mandate the use of RFIDs for tracking waste shipments.
David Zuwala, RFID architect at Dow Corning, said he had similar EPA requirements for using RFID to track chemicals stored in 55-gallon drums at one of the company's plants. He said that based on his experience, the agency is not asking for too much with its 100 percent read-rate requirement.
Zuwala said he achieved a 100 percent read rate on forklifts moving pallets containing four 55-gallon metal drums with special tags from Avery Dennison through XR440 portal readers manufactured by Symbol Technologies, which is now part of Motorola.
He said he achieved the best read rate by affixing tags vertically on the drums, using two antennas on the portal, and providing visual clues to the forklift operator on how to maneuver through the portal to get the best read rate.
Ed Tan, a Motorola spokesman, said his company viewed the EPA pilot project as "definitely a worthwhile technical [and] operational investigation," and believes that leaving the technology configuration to industry is the best approach.
If EPA decides to field RFID to track shipments of toxic waste, Kopsick said she could envision a nationwide network at Canadian and Mexican border crossings, as well as truck weigh stations, providing the agency with real-time visibility into the movement of hazardous waste nationwide.
She said EPA has coordinated the planned RFID test with the Mexican government, "which also wants to know what waste crosses it borders," and expects an observer from the Canadian government will be at the Santa Teresa test.