Hazardous wastes containment problems

Metal reclamation of sediments uses many of the same approaches as for soils, except that sediment access is often more difficult. Once removed from the bottom of a lake or river, sediments can be treated and replaced, or landfilled in a hazardous waste containment site. The actual removal of sediments involves dredging. This can pose serious problems since dredging includes the excavation of sediments from benthic anaerobic conditions to more atmospheric oxidizing conditions. This can result in increased solubilization of metals, along with increased bioavailability (see Section 10.3) and potential toxicity, and increased risk of contaminant spreading (Moore, Ficklin Johns, 1988 Jorgensen, 1989 Moore, 1994). There are ongoing discussions as to whether it is more detrimental to remove sediments, whether for treatment or removal, or simply to leave them in place. 

This past decade has seen rapidly growing concern for the problems caused by hazardous wastes. Containment of such wastes will demand more and more attention in the coming years. Grouting and other procedures can... 

In the laboratory when it comes to hazardous waste, the really important issue is identifying the contents of your hazardous waste. We can hear you groaning now. Why do I need to worry about this stuff, after all it s just waste and I just want to get rid of it. Well, so does your institution. However, if the contents of a hazardous waste container are not labeled, that is, unknown—well, as Tom Hanks said in Apollo 13, Houston, we have a problem. Well, maybe it s not the same magnitude as a marooned astronaut but it is a very real problem. 

In the mid-1980s, the city of Philadelphia was experiencing a problem common to many urban areas in the United States. The city had run out of places to dispose of some of its solid wastes. One hatch of wastes that posed a special problem consisted of ash produced at the city s Roxhorough incinerator. These wastes contained hazardous chemicals, which made them unacceptable to other "host states, such as Ohio, Virginia, South Carolina, and Georgia, which had been receiving wastes from other urban areas on the East Coast. 

The solid wastes produced by industrial operations pose a problem similar to that of municipal solid wastes simply the volume of waste produced annually. The volume of industrial solid wastes generated in the United States is roughly twice that of MSW, about 570 million short tons (518 million metric tons) in 2000. But industrial solid wastes also pose a very different kind of problem in that they also contain a number of chemical elements and compounds that are hazardous to the health of humans, other animals, and plants. These elements and compounds are classified as hazardous wastes. Hazardous wastes pose a variety of technological, economic, and... 

Specifically, catalysts are typically in the form of a ceramic support carrying small amounts of metals such as chromium, nickel, or platinum. Alumina and silica are commonly used in the construction of the ceramic support. Die catalysts lose their activity progressively via various deactivation mechanisms (Pavel and Elvin, 1994). Tliermal regeneration is often employed for regaining catalytic activity, if applicable, but some of the particles break during this process. Once the catalyst particles become too small to be useful, they constitute a waste disposal problem, since catalysts may contain heavy metals that are considered hazardous, or other harmful components. 

Stabilization (1) Stage of an incident when the immediate problem or emergency has been controlled, contained, or extinguished. (2) Hazardous waste chemical treatment method by which a chemical reaction produces an insoluble form of tire waste or incorporates the waste into a form that is insoluble. 

Recall Problem 3.1. You are the boss of an analytical laboratory and, this time, you check the numbers from the analysis of chlorobenzene in water samples of very different origins, namely (a) moderately contaminated groundwater, (b) seawater ([salt]tot 0.5 M), (c) water from a brine ([salt]tot = 5.0 M), and (d) leachate of a hazardous-waste site containing 40% (v v) methanol. For all samples, your laboratory reports the same chlorobenzene concentration of 10 ng IT1. Again the sample flasks were unfortunately not completely filled. This time, the 1 L flasks were filled with 400 mL liquid, and stored at 25°C before analysis. What were the original concentrations (in /J,g-L l) of chlorobenzene in the four samples ... 

While there may be many options to deal with RO reject, each one has advantages and limitations. Some offer cost savings, while others may increase costs, but eliminate the need to dispose of a relatively large waste stream. Reject is considered non-hazardous, and contains only those constituents that were present in the feed water (only more concentrated, which can be a problem) and any antisealants, biocides (such as DBNPA—see Chapter 8.2.5.2), or any other chemical added as pretreatment. Disposal techniques over the years have included ... 

Location of buried materials at a hazardous waste site is usually for the purpose of remedial action l.e., excavating these materials and ultimately disposing of them. The key unknowns are type (bulk-dumped or packaged in drums or other containers), quantity (volume of waste number of drums), and location, particularly depth of burial. The concerns are for safe excavation without puncturing containers or breaching any existing trench liners and thus aggravating the cleanup problems. 

It is not known if exposure to uranium has effects on the development of the human fetus. Very high doses of uranium in drinking water can affect the development of the fetus in laboratory animals. One study reported birth defects and another reported an increase in fetal deaths. However, we do not believe that uranium can cause these problems in pregnant women who take in normal amounts of uranium from food and water, or who breathe the air around a hazardous waste site that contains uranium. 

One type of hazardous waste is unique a harmless solid that is damp with an organic solvent. Alumina from a chromatography column or sodium sulfate used to dry an ether solution are examples. Being solids they obviously can t go in the organic solvents container, and being flammable they can t go in the nonhazardous waste container. A solution to this problem is to spread the solid out in the hood to let the solvent evaporate. You can then place the solid in the nonhazardous waste container. The saving in waste disposal costs by this operation is enormous. 

It was clear as soon as it was passed that CERCLA would address only the most serious sites and that there were literally thousands of other sites containing hazardous wastes that also needed to be dealt with. In the absence of federal resources for this task, a number of states passed their own legislation to identify, assess and remediate such sites. Activities undertaken under both the federal and state statutes revealed that hazardous wastes had been buried not only in industrially owned sites but also in municipal and private landfills. Indeed, some of these hazardous wastes were the result of citizen disposal practices. Thus, the dimensions of the problems that Love Canal uncovered were revealed to be larger than first thought and the resources needed to address them much greater than anticipated. Twenty-five years later, these problems persist and many sites still await remediation. 

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