Hazardous materials closure

The JACADS closure activities will involve the dismantling and destruction of that portion of the facility that cannot be decontaminated to meet the 5R cleanliness standard. An area decommissioning matrix delineates the areas that will be decontaminated and dismantled, decontaminated and abandoned in place, or solely abandoned in place (U.S. Army, 2000c). The remaining systems, structures, and components (SSCs) that are left in place must meet the Resource Conservation and Recovery Act (RCRA) criteria for decontamination as well as the Army standard of 5R. Areas that were kept free of any agent or hazardous materials will be sampled to demonstrate their cleanliness in accordance with the final closure sampling and analysis plan. 

The Decontamination Report provides an overall strategy for removing hazardous materials from the MDB, SWMUs, and AOls. A contamination investigation (RFI), yet to be completed, will provide the detailed characterization data to support closure activities. The characterizations will be based in part on analysis of concrete core borings taken from selected locations. 

Essentially all solidified hazardous chemical waste is intended for disposal in near-surface facilities, with prescribed actions to prevent unacceptable releases of hazardous material (e.g., leachate collection and treatment). However, these facilities have been developed and operated essentially without consideration of the potential long-term risks posed by the waste in the absence of active monitoring and maintenance, including potential risks to future inadvertent intruders, or the requirements on site closure and release from institutional control that would ensure long-term protection of public health and the environment. 

In addition, damage to the environment is important. Hazardous materials may contaminate groundwater and water supplies, cause the closure of wells, destroy namral habitats, contaminate soil, kill fish or livestock, incapacitate sanitary sewer treatment facilities, damage crops, or contribute to air pollution. Hazardous waste may also have biohazards, covered under toxicity. 

We can expect drastic changes in the food packaging industry. Some will arise from new consumer needs, new or expanded food supplies and products, and new food preservation systems such as aseptic packaging. Others will result from societally based constraints such as safety in health and hazardous use (as in the child safety closure legislation) and consumer protection against fraud, misinformation, or wrongful use where the burden for awareness is no longer on the buyer but on the supplier. Other such constraints will arise from environmental concerns or material scarcities. 

Filter layers, frost penetration, and cap-liner connections are other factors to consider in designing the closure system for a hazardous waste landfill. Before using geotextiles for filter layers in closures, one should conduct pressure tests and clogging tests on the material. Freeze-thaw cycles probably have little effect on membranes, but their impact on clay is still not known. Because of this lack of knowledge, membrane and clay layers should be placed below the frost penetration layer. Finally, a cap membrane should not be welded to the primary FML. Differential settlement in the cap can put tension on the cap membrane. In such a situation, the seam could separate and increase the potential for integration of the surface water collection system into the LDS. 

Finding 4. The closure plan is incomplete in that it does not sufficiently address contingencies such as control of spills, dust, or special materials such as asbestos, nor does it specify countermeasures for mitigation of these potential situations. Moreover, the hazardous waste management units (HWMUs) at JACADS and the Red Hat Storage Area differ in the chemicals to be analyzed, their management and associated... 

Relief valves are preferred for use on clean materials, because automatic closure prevents excessive discharge once excessive pressure is relieved. Rupture disks are less susceptible to plugging or other malfunctions but may allow complete emptying of the vessel, thus creating a safety or environmental hazard. Where fluctuating pressures or very corrosive conditions exist, or where polymerizable materials could prevent proper operation of a relief valve, some designers install two safety devices in series, ie, either two rupture disks or an upstream rupture disk followed by a relief valve. With either arrangement, it is imperative that the space between the two relief devices be monitored so that perforation or failure of the relief device closest to the vessel may be detected (86). 

Plastic components (whether container or closure) can be sterilized using steam, ethylene oxide, hydrogen peroxide, or ionizing radiation. The y irradiation is accomplished off-site by a subcontractor with appropriate expertise as these methods are considered the province of specialists because of the extreme health hazards directly related to the sterilization method. Electron beam sterilization may also be done by a contractor, although compact lower energy electron beam systems have been introduced that allow sterilization in-house. Steam sterilization is ordinarily performed in house, though many common components are becoming available presterilized by the supplier. Preparation steps prior to sterilization vary with the component and the methods used to produce the component. Rubber components are washed to reduce particles, while this is less common with plastic materials. 

Bianchi, M. A., R.J. Portier, K. Fujisaki, C.B. Henry, P.H. Templet, and J.E. Matthews. 1988. Determination of optimal toxicant loading for biological closure of a hazardous waste site. In Aquatic Toxicology and Hazard Assessment, Vol. 10, ASTM STP 971. W.J. Adams, G.A. Chapman, and W.G. Landis, Eds. American Society for Testing and Materials, Philadelphia, PA, pp. 503-516. 

The stackability of finished stock is a final factory consideration prior to the evaluation of transit hazards—fortunately, glass is a strong material and can take at least part of the stacking pressures. Dangers therefore relate to the effect on the closure rather than the container. Undue pressure can be transmitted to the cap wad, thus inducing a compression set which reduces the seal efficiency. Compression and transit vibration may also increase such an effect to the point of closure failure. 

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