People from across the nation came to Edwards on May 14 to see a new perchlorate treatment system being tested here. Associated with the use of rocket fuels at Edwards, perchlorate can cause thyroid problems and is a contaminant of concern nationwide.
Approximately 80 people representing the Department of Defense, federal, state and regional regulatory agencies and environmental contractors attended Perchlorate Day at Edwards, where a selective ion exchange resin technology developed by Oak Ridge National Laboratory (ORNL) in Tennessee was introduced and demonstrated.
For the next year or more, Edwards will be evaluating the cleanup effectiveness and cost efficiency of the resin technology during a treatability study at Site 285. The ORNL resin has the ability to select only perchlorate for removal from groundwater. The resin system can then be flushed with an acid solution and reused. This is the first known full-scale treatment study using the technology for perchlorate-contaminated groundwater.
'The Perchlorate Day turnout was the best we've seen,' Site 285 project manager Paul Schiff said. 'That is because of the attention being placed on perchlorate nationwide and the fact that this is a relatively new contaminant of concern for which there is no cleanup standard established yet.'
Perchlorate Day guests visit Site 285 where the Air Force is testing a leading-edge technology that selectively removes the contaminant perchlorate.
Baohua Gu, Ph.D., Environmental Sciences Division at ORNL, is the mastermind behind the resin beads that are designed to extract the perchlorate ion from ground or surface water.
Testing of resin beads at Edwards is giving Gu and ORNL a chance to prove the new perchlorate removal technology's worth in a real-world setting. Edwards is considered to be a good place to demonstrate the technology's potential for total destruction of perchlorate on site.
At Site 285, groundwater is pumped from the contaminated area through filters that remove initial impurities. It then travels through a series of three selective ion exchange resin vessels. The system also provides a granulated active carbon filter for final scrubbing, if needed. Afterward, the groundwater is recirculated into the ground.
The Air Force granted a waiver to test the new resin technology at Edwards largely because of persistence shown by the base's Restoration Advisory Board, or RAB.
'It was the RAB that kept our focus on these kinds of sites,' said Robert Wood, director of Environmental Management. 'Normally, until cleanup benchmarks for perchlorate were established, perchlorate would have gone untreated at Edwards. But the RAB made their concerns heard.'
The resin system is located on the former National Aeronautics Space Administratio/ Jet Propulsion Laboratory (NASA/JPL) at Edwards. As solid propellant was cut into its desired size and shaped for test firings, the dust and shavings were discarded into catch tanks and leach fields and the perchlorate made its way into the groundwater.
According to the United States Environmental Protection Agency, perchlorate (CIO4-) is a chemical both naturally occurring and man-made. Most of the perchlorate manufactured in the United States is used as the primary ingredient in solid rocket propellant. Wastes from the manufacture and improper disposal of chemicals that contain perchlorate are increasingly being discovered in soil and water across the nation.
Attending Perchlorate Day at Edwards were representatives of the Army, Navy and others from the Department of Defense; various regulatory agencies including U.S. EPA, California EPA/ Department of Toxic Substances Control Regional Water Quality Control Board and Kern County Environmental Health Services Department; and environmental contractors including Shaw Environmental, TetraTech, Calgon Carbon and others.
Prior to making a site visit, Schiff and others gave an informative presentation about the site. Earth Tech geologist Todd Battey explained the technology and ERP project manager Ai Duong discussed the perchlorate issues at the Edwards Air Force Research Laboratory facility.
'At Edwards Air Force Base, we test things until they fail. That's how we know what the aircraft or a technology such as this can do,' Wood said. 'This technology may not do everything we expect of it, but that's the reason we have treatability studies, to determine the cost and performance data for the system so that we and others can learn from our experience.'
The experimental technology cost $800,000, and has been running intermittently since March 2003. The ERP expects the treatment study will last approximately one to two years.