Technology created hazards

U.S. Environmental Protection Agency. Technology transfer network air toxics Web site. 1999. Acrylonitrile. Hazard summary created in April 1992. Revised in January... 

The environment in which exposure to hazards is created, mitigated.or eliminated, and where adverse events occur or are prevented. Not just the bedside and other clinical settings but also the laboratory, magnetic resonance imaging unit, hallway,patient shuttles, etc.- any place staff, patients,and. or technology interact... 

U.S. EPA promulgated MACT standards for most HWCs on September 30, 1999. These emission standards created a technology-based national cap for HAP emission from the combustion of hazardous waste in these devices. A number of parties, representing both industrial and environmental communities, requested judicial review of this rule, and challenged its emission standards and several implementation provisions. On July 24,2001, the United States Court of Appeals for the District of Columbia Circuit vacated the emission standards however, it allowed EPA to promulgate interim standards that were in place since February 13, 2002. U.S. EPA issued the new Final Rule and standards on April 20, 2004. Today s standards30 31 shown in Tables 23.5 and 23.6 result from the above judiciary and regulatory actions. 

The Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), commonly known as Superfund, 1980, created a tax on the chemical and petroleum industries and provided broad federal authority to respond directly to releases or threatened releases of hazardous substances that may endanger public health or the environment. The act was amended by the Superfund Amendments and Reauthorization Act (SARA) in 1986 and stressed the importance of permanent remedies and innovative treatment technologies in cleaning up hazardous waste sites. 

The PF technology also has several potential limitations. Fractures do not always propagate in the direction or to the distances expected. Fractures may open new pathways for the unwanted spread of contaminants. Pockets of low permeability may remain after fracturing. Surface heave and stress resulting from the process can create hazards for buildings or other structures at a site. If the moisture content of the contaminated media is not controlled, the formation may swell and close the fractures. PF is not applicable at sites with high natural permeabilities. Fractures will close in soils with low clay content. In addition, PF should not be used in areas of high seismic activity. 

Following biological degradation, the extract is exposed to photochemical degradation, which removes uranium from solution as polyuranate. The metals and uranium are captured in separate treatment steps, allowing for the separation of wastes into radioactive and nonradioactive waste streams. This treatment process does not create additional hazardous wastes and allows for the reuse of the contaminated soil. The technology has been the subject of bench-scale tests and is not currently commercially available. 

This technology does not change any hazardous characteristics of the waste it creates a more concentrated waste for further treatment or disposal. 

Perma-Fix Environmental Services, Inc. (Perma-Fix), has developed the Perma-Fix Process for the neutralization and stabilization of hazardons, radioactive, and mixed wastes. The Perma-Fix Process is a two-step treatment involving proprietary chemical treatment of wastes followed by the addition of stabilization chemicals to create a final waste form with the hazardous component of the wastes neutrahzed. The technology has been used commercially for several years. 

Polymer-based stabilization/solidification (S/S) is a technology for the ex situ treatment of radioactive, mixed, and hazardous wastes. It is a process in which polymers are created within the waste matrix to solidify and physically immobilize the hazardous constituents of contaminated materials. The goal is to prevent the migration of contaminants into the environment by forming a solid mass. 

All solvent extraction technologies use flammable organic extraction fluids that present potential fire and explosion hazards. Several of the extraction fluids include volatile or semivolatile compounds, which can create explosive vapor mixtures. A number of the extraction fluids contain toxic organic compounds therefore, process designs must minimize or eliminate personnel exposure to these compounds. 

One of the main components of the HSWA is the land disposal ban for hazardous wastes. This land ban states that no hazardous waste can be disposed of on land until it has been treated to have concentrations of chemicals under a certain level. The USEPA was given the responsibility to create these levels and provide a proper treatment method for each waste. The universe of hazardous waste was broken down into three categories these groups of waste were evaluated, and specific treatment methods and standards were developed. The treatment standards have been based primarily on available technology rather than on potential risks (Hendrichs, 1991). If, after treatment, the waste no longer meets any of the criteria under which the waste was listed, it can be unlisted. This process requires an extensive petition to be filed with the USEPA and can take several years to be approved. 

The USEPA is responsible for creating and enforcing the NESHAPs for all hazardous air pollutant sources. The CAA states that new or existing major sources must have emission standards based on the maximum available control technology (M ACT) to reduce hazardous air pollutant emissions. The MACT standards are based on the performance of the best 12% of the control devices in the same source category. These MACT emissions requirements were extended in 1997 to cover wastewater biosolid incinerators at publicly owned treatment works (POTWs) that have the potential to discharge cadmium, lead, and mercury (Richman, 1997). 

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