Hazardous or radioactive

Underground chambers are also constructed in frozen earth (see subsection Xow-Temperature and Cryogenic Storage ). Underground tunnel or tank storage is often the most practical way of storing hazardous or radioactive materials. A cover of 30 m (100 ft) of rock or dense earth can exert a pressure of about 690 kPa (100 Ibf in"). 

Tons of earth per hour can be sifted and scrubbed clean of hazardous materials by using what may be called a heavy-duty industrial washing machine. Soils contaminated with hazardous or radioactive materials may... 

In most waste streams, either hazardous or radioactive, only a small amount of harmful contaminants is found in a large volume of otherwise harmless waste, and the treatment is aimed at reduction of the effect of these contaminants on the environment. Possible treatments include separation and recycling of the contaminants, destruction of the waste, and if these methods fail, isolation of the entire waste volume and disposal or safe storage. The decontamination and recycling of waste is a good strategy, provided it is economical. Where recycling is not economical, destruction of the wastes takes precedence over any... 

Class IV Injection of hazardous or radioactive waste into or above USDW. 

Standard industrial hazards (e.g., electrocution, handling accidents) are developed in the PHCs only to the extent that they are initiators and contributors to accidents that could potentially lead to the release of hazardous or radioactive material. Although major, non-contributory industrial accidents are identified in the PHCs, these hazards are screened from further evaluation. 

Class IV wells may inject hazardous or radioactive wastes into or above a USDW and are banned imless specifically authorized under other statutes for ground water remediation. 

C. Result in serious personnel injury or significant lost workday cases personnel contamination, assimilation, exposure or significant onsite or offsite contamination of hazardous or radioactive materials in excess of administrative limits but within regulatory limits or degradation of environmental monitoring equipment necessary to demonstrate compliance ... 

Industrial refractories are by thek very nature stable materials and usually do not constitute a physiological hazard. This is not so, however, for unusual refractories that might contain heavy metals or radioactive oxides, such as thoria and urania, or to bkiders or additives that may be toxic. 

Deactivation and D D actions can range from stabilization of multiple hazards at a single site or facilities containing chemical or radioactive contamination, or both, to routine asbestos and lead abatement in a nonindustrial structure. Strategies include programs that meet compliance objectives, protect workers, and make certain that productivity and cost-effectiveness are maintained. The content and extent of health and safety-related programs should be proportionate to the types and degrees of hazards and risks associated with specific operations. 

The chemistry, and hence hazards, of hot, or radioactive, elements parallels that of their cold isotopes. However, the radiation poses additional toxicity hazards. A qualitative classification of selected isotopes in terms of their toxicity is given in Table 10.2. The biological effects of ionizing radiation stem mainly from damage to individual cells following ionization of the water content. Oxidizing species, e.g. hydrogen peroxide. 

Independent of combustibility or reactivity, chemicals may exhibit hazardous properties that affect fire protection, in particular firefighting. Chemicals may be inherently toxic or radioactive. In either situation, potential exposure of smoke/gases to personnel from the burning of materials exhibiting these characteristics needs to be addressed. 

The systems produce no harmful emission, harmful or radioactive byproducts, hazardous wastes, or biospheric pollutants. As usage is phased in worldwide, a significant reduction of environmental pollutants and hazardous wastes will result, as will a cleaner biosphere. 

Do not use the microwave oven to heat up hazardous chemicals or radioactive materials. 

Establishing an acceptable risk or dose. There also are a number of precedents for establishing an acceptable (barely tolerable) risk or dose of substances that cause stochastic responses for the purpose of classifying waste as low-hazard or high-hazard. For radionuclides, the annual dose limit for the public of 1 mSv currently recommended by ICRP (1991) and NCRP (1993a) and contained in current radiation protection standards (DOE, 1990 NRC, 1991) could be applied to hypothetical inadvertent intruders at licensed near-surface disposal facilities for low-hazard waste. This dose corresponds to an estimated lifetime fatal cancer risk of about 4 X 10 3. Alternatively, the limits on concentrations of radionuclides in radioactive waste that is generally acceptable for near-surface disposal,... 

The hazardous waste classification system recommended by NCRP is depicted in Figure 6.1 at the beginning of Section 6. This proposal was developed with two fundamental objectives in mind. First, all wastes that contain radionuclides, hazardous chemicals, or mixtures of the two should be included in the same classification system. A comprehensive hazardous waste classification system should be developed to replace the separate, and quite different, classification systems for radioactive and hazardous chemical wastes, as well as the separate classification systems for radioactive waste that arises from operations of the nuclear fuel cycle and NARM waste. Second, all hazardous wastes should be classified based on considerations of risks to the public that arise from disposition of the material. In this Report, permanent disposal in a permitted facility for hazardous or nonhazardous waste is the assumed disposition of waste containing hazardous substances that has no further use to its present custodian. An important consequence of these two objectives is that the same rules should apply in classifying any waste that contains hazardous substances. 

At the present time, there is essentially only one class of hazardous chemical waste (i.e., a waste either is hazardous or it is not), without regard for the amounts of hazardous substances in the waste. Establishment of a risk-based waste classification system would allow for the possibility of two classes of hazardous chemical waste based on the amounts of hazardous substances, consistent with the present situation for radioactive waste, with the attendant implication that high-hazard chemical waste that contains the highest amounts of hazardous substances would require a disposal technology substantially more isolating than a near-surface system. 

The transport rates of substances in river water are of economic importance, e.g. in potentially hazardous or pollution incidents. These transport rates have usually been measured by expensive tracer experiments with salts, colored compounds, or radioactive isotopes which can themselves be pollutants if the measurements are repeated frequently. 

It is advised that you wear latex or vinyl exam gloves at all times in the laboratory. Even if a particular experiment does not require the use of hazardous chemicals, one can never be sure that those from a previous experiment have been properly disposed of. If volatile compounds are used, they should be stored under a fume hood at all times. If possible, students should work with these materials under the fume hood as well. The large amounts of materials that are often required for a laboratory group may soon fill the room with unpleasant and potentially hazardous vapors. This is particularily important if the reagent vapors are flammable (see Experiment 6) or radioactive (see Experiment 12). 

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