National Academies' Report Recommends Off-site Disposal for Secondary Waste
A new report by the National Academies' National Research Council find that much of the secondary waste produced during the U.S. Army's chemical agent destruction program can and should be dealt with at off-site facilities while destruction operations are carried out.
The committee that wrote the report, released on July 26, also determined that the provision in the Resource Conservation and Recovery Act (RCRA) allowing the submission of data from previous trial burns -- test runs required to prove the effectiveness of incinerators in destroying certain agents -- in lieu of new trial burns should be used to the fullest extent possible.
"The Army's incinerators are destroying the United States' stockpiled chemical weapons, but the on-site capacity is just not enough for treating high volumes of secondary wastes such as carbon, wood dunnage, or protective gear," said committee chair Peter B. Lederman, retired executive director of the Hazardous Substance Management Research Center, Newark, N.J. "Destroying the secondary waste concurrently at off-site locations whenever appropriate will dramatically improve closure operations."
The committee reviewed the waste disposal practices at all of CMA's currently operating incinerator facilities, located in Anniston, Ala., Pine Bluff, Ark., Umatilla, Ore., and Tooele, Utah, as well as the chemical neutralization facility in Newport, Ind. In evaluating the sites, the committee also drew from the experiences of the 2003 closure of the Johnston Atoll Chemical Agent Disposal System (JACADS) in the Pacific, which suffered from substantial increases in costs and delays due to thousands of tons of secondary waste that had accumulated on-site.
Current waste management at the facilities is regulated by state-issued permits that date back to before the construction of the facilities, when data concerning the quantities of wastes was scarce. While the permits have been modified somewhat since then, great disparity still exists between how each site manages waste. For instance, in three of the five states, all waste from chemical agent disposal operations is considered hazardous, regardless of whether it exhibits hazardous characteristics. Managing waste listed as hazardous is more challenging because of added restrictions on shipping, storage and disposal procedures. Commercially run hazardous waste management facilities can provide relief from the on-site disposal capacity problem and typically have far greater waste treatment and disposal capacity. The committee noted that changes to allow more off-site treatment and disposal will in most cases require modifications to the site operating permits.
The committee focused its review on six major waste streams that result from the destruction of chemical agents: spent activated carbon, brine solutions and salts, wood dunnage, scrap metal, plastics, and spent decontamination solutions. These secondary wastes are found in different quantities at all four incinerator locations. The chemical neutralization facility does not generate brine solutions or salts; instead it generates VX hydrolysate, a water-based liquid resulting from the chemical breakdown of the VX nerve agent. Excluding the hydrolysate and wastes that can be eliminated on-site, CMA estimates that there will be more than 10 million pounds of secondary wastes at the completion of the chemical weapons destruction operations.
Spent activated carbon represents nearly 35 percent of the estimated secondary wastes. Activated carbon beds are used in the pollution abatement filtration systems, which treat the air in the on-site buildings and all gases that emanate from the disposal process. The carbon absorbs contaminants from the air and byproduct gases, preventing their escape into the environment. The system requires constant monitoring and frequent changing of the carbon beds. The committee found that on-site treatment of the carbon followed by its incineration has been problematic at best, and recommends that off-site disposal, decontamination, and destruction of the spent activated carbon should be pursued whenever possible.
Brine solutions are used to treat the gases arising from the incinerators. The solutions contain salt, water, suspended solids, and trace amount of heavy metals. The committee found that this type of waste is already disposed of off-site, and recommended that CMA continue to actively dispose of as much brine solution or salts off-site as possible.
Dunnage includes pallets and wood used to store the munitions. Generally, this waste is nonhazardous and can be easily disposed of through removal to an off-site facility. If exposed to a contaminant, the dunnage can be incinerated on-site. The report notes, however, that "there are no simple, direct, and reliable analytical techniques for determining contaminants that may be absorbed into the dunnage," and recommends that CMA improve techniques to enable more exact measurements of possible contamination to meet off-site shipping criteria and reduce the amount of waste dealt with on-site.
Scrap metal from the munitions casings and bulk containers is thermally treated to ensure destruction of any contaminants and stored temporarily on-site before shipment to an external disposal or recycling facility. The report recommends that scrap metal continue to be recycled or disposed of off-site as much as possible.
Plastics, in the form of the protective suits used in the facilities, can be disposed of on-site or off through treatment and then incineration. However, the report indicates that the capacity for on-site disposal is severely limited, and recommends CMA pursue off-site shipment, as long as it adheres to and enforces packing, shipping, monitoring, and treatment restrictions.
Decontamination solutions are used to wash work areas and decontaminate workers prior to removal of their suits. They are analyzed for contaminants, treated if necessary, and disposed of either on- or off-site. The committee found that disposal of these spent solutions does not present a significant challenge for the currently operating facilities, and so does not require any changes at this time.
In addition to secondary wastes, the report examines the regulatory requirements associated with trial burns at the incinerator facilities. Trial burns are used to ensure that 99.9999 percent of the toxic agents will be destroyed during regular operations. The time required to complete a trial burn, submit results, and obtain authorization for full operation can be very lengthy due to the time required to actually conduct the burn and the large amount of data that must be submitted and analyzed. However, under RCRA, which governs the disposal operations, these trials can potentially be avoided through the submission of data from a trial burn conducted in a sufficiently similar incinerator burning the same agent.
The committee found that because a trial burn has occurred for each type of incinerator with each agent, enough data exists to avoid further trial burns in many cases. The report recommends using this process of data submission in lieu of a trial burn to the fullest extent possible. The committee also recommends that the CMA should try to provide funding to state authorities for third-party analysis of trial burn data to shorten the time necessary for approval.
The report, "Review of Chemical Agent Secondary Waste Disposal and Regulatory Requirements," can be accessed at http://books.nap.edu/catalog.php?record_id=11881.
This article originally appeared in the 07/01/2007 issue of Environmental Protection.