Contamination waste disposal sites

FIGURE 17.30 This 35-year-old drum of radioactive waste has corroded and leaked radioactive materials into the soil. The drum was located in one of the nuclear waste disposal sites at the U.S. Department of Energy s Hanford, Washington, nuclear manufacturing and research facility. Several storage sites at this facility have become seriously contaminated. 

The most important routes of exposure to endosulfan for the general population are ingestion of food and the use of tobacco products with endosulfan residues remaining after treatment. Farmers, pesticide applicators, and individuals living in the vicinity of hazardous waste disposal sites contaminated with endosulfan may receive additional exposure through dermal contact and inhalation. 

Sources of land pollution include direct dumping of domestic and industrial solid waste, excessive application of agrochemicals, and indirect contamination resulting from leaks or from leaching of hazardous components from liquid waste disposal sites or from atmospheric fallout. Land may also become contaminated by chemicals processed, stored or dumped at the site, perhaps in the distant past. Such contamination may pose a health risk to workers on the site, those subsequently involved in building, construction or engineering works, or the public (e.g. arising from trespass), and to animals. 

Trichloroethylene enters your body when you breathe air or drink water containing it. It can also enter your body if you get it on your skin. You could be exposed to contaminated water or air if you live near or work in a factory that uses trichloroethylene or if you live near a waste disposal site that contains trichloroethylene. If you breathe the chemical, about half the amount you breathe in will get into your bloodstream and organs. You will exhale the rest. If you drink trichloroethylene, most of it will be absorbed into your blood. If trichloroethylene comes in contact with your skin, some of it can enter your body, although not as easily as when you breathe or swallow it. 

In a rural area, where leachate from a hazardous waste disposal site has contaminated an aquifer currently used by only a few residential wells, it may appear more cost-effective to replace a water... 

The first commercial trialkyl phosphate esters (TAP) were tricresyl phosphate (TCP) and trixylenyl phosphate (TXP), referred to as "natural" phosphate esters because the cresols and xylenols used as raw materials are derived from petroleum oil or coal tar (Marino and Placek 1994). These products are not commercially significant at present however, at waste disposal sites, contaminants from older product formulations may be encountered, particularly those containing the neurotoxic tri-o/T/io-cresyl phosphate isomer. "Synthetic" phosphate esters are derived from synthetic feedstocks. Specific synthetic reactions have been developed to produce triaryl, trialkyl, and alkyl Aryl esters. The triaryl phosphates are currently... 

One of the main human health concerns about organophosphate esters is the potential for neurotoxicity reactions, in particular a condition known as organophosphate-induced delayed neurotoxicity (OPIDN). Tri-ort/20-cresyl phosphate (TOCP) has been identified as one of the more potent OPIDN neurotoxins in humans, and was formerly a constituent in some organophosphate ester hydraulic fluid products (Marino 1992 Marino and Placek 1994). Production processes now routinely remove virtually all the TOCP. For instance, tricresyl phosphate (TCP) products now typically are manufactured to contain over 98% meta and para isomers and virtually no TOCP (Marino and Placek 1994). Products containing these compounds associated with OPIDN have now entirely disappeared from commercial use, and the vast majority of the industrial organophosphate esters are based on triaryl phosphates with no halogenated components (Marino 1992). At waste disposal sites, however, site contaminants from older product formulations containing the ortho form may be encountered. 

Before the 1960s, products were introduced based on alkyl aryl phosphates that could contain chlorinated aromatic hydrocarbons. Such products have now entirely disappeared from commercial use, and the vast majority of the industrial organophosphate esters are based on triaryl phosphates with no halogenated components (Marino 1992). However, at older waste disposal sites, hydraulic fluid site contaminants could contain chlorinated hydrocarbons. As with the PCBs formerly included as additives in other forms... 

Table 1 indicates primary pollutant sources and waste modes, and Table 2 indicates the primary and secondary sources and associated pollutants. The primary sources of soil contamination include land disposal of solid waste sludge and waste-water industrial activities and leakages and spills, primarily of petroleum products. The solid waste disposal sites include dumps, landfills, sanitary landfills, and secured landfills. 

The fact that endrin is no longer produced or used in the United States greatly reduces the potential for human exposure. Future levels of endrin, endrin aldehyde, and endrin ketone in environmental media are expected to be low. The most significant route of exposure is most likely ingestion of imported foods contaminated with endrin however, there may also be some localized risks from exposures near waste disposal sites or from groundwater contaminated with endrin. 

Endrin has also been shown to be absorbed after ingestion by humans (Coble et al. 1967 Curley et al. 1970 Kintz et al. 1992 Rowley et al. 1987 Runhaar et al. 1985 Waller et al. 1992 Weeks 1967) however, no studies were located on the rate or extent of absorption that occurs in orally exposed humans or animals. Exposure to endrin through ingestion of contaminated drinking water is not expected to be an important source of concern because the compound has only rarely been detected in drinking water (Schafer et al. 1969 Wnuk et al. 1987). Since endrin is tightly bound to soil particles, ingestion of endrin-contaminated soil, particularly by children, may be an important route of exposure near hazardous waste disposal sites that contain endrin. 

The injection of produced water and other oil held fluids into wells started as early as 1928. In 1976, more than 300 industrial waste disposal sites were in operation throughout the country. By 1986, approximately 60 million barrels of oil held fluids were injected through 166,000 injection wells within the conterminous United States. These volumes are anticipated to increase significantly in the future as producing helds continue to be depleted. Thus, construction requirements as listed in 40 CFR 146.22 are an essential prerequisite to the safe disposal/injechon of fluids and the prevention of contamination of USDW. 

As a result of human health concerns, production of mirex ceased in 1976, at which time industrial releases of this chemical to surface waters were also curtailed. However, releases from waste disposal sites continue to add mirex to the environment. Virtually all industrial releases of mirex were to surface waters, principally Lake Ontario via contamination of the Niagara and Oswego Rivers. About 75% of the mirex produced was used as a fire retardant additive, while 25% was used as a pesticide. As a pesticide, mirex was widely dispersed throughout the southern United States where it was used in the fire ant eradication program for over 10 years. 

Production of chlordecone ceased in 1975 as a result of human health concerns at that time industrial releases of this chemical to surface waters via a municipal sewage system were curtailed. However, releases from waste disposal sites may continue to add chlordecone to the environment. Major releases of chlordecone occurred to the air, surface waters, and soil surrounding a major manufacturing site in Hopewell, Virginia. Releases from this plant ultimately contaminated the water, sediment, and biota of the James River, a tributary to the Chesapeake Bay. 

Mirex has been detected in air, surface water, soil and sediment, aquatic organisms, and foodstuffs. Historically, mirex was released to the environment primarily during its production or formulation for use as a fire retardant and as a pesticide. There are no known natural sources of mirex and production of the compound was terminated in 1976. Currently, hazardous waste disposal sites and contaminated sediment sinks in Lake Ontario are the major sources for mirex releases to the environment (Brower and Ramkrishnadas 1982 Comba et al. 1993). 

Mirex is no longer manufactured, formulated, or used in the United States. Therefore, there is currently no occupational exposure to this chemical associated with its production or application as a pesticide. Current occupational exposure is most likely to occur for workers employed at waste disposal sites or those engaged in remediation activities including removal of soils and sediments contaminated with mirex. There is a slight possibility of exposure for workers involved in dredging activities (e.g., sediment remediation work performed by the Corps of Engineers). 

Current occupational exposure is most likely to occur for workers employed at waste disposal sites or those engaged in remediation activities associated with the clean-up or removal of soils or sediments that are contaminated with chlordecone. 

In addition, the Superfund Amendments and Reauthorization Act (SARA) of 1986 set the groundwater standards the same as the drinking water standards for the purpose of necessary cleanup and remediation of an inactive hazardous waste disposal site. The 1986 amendments of the SDWA included additional elements to establish maximum contaminant-level goals (MCLGs) and national primary drinking water standards. The MCLGs must be set at a level at which... 

While there are no precise data on extent of environmental contamination in Eastern Europe, it has been estimated that the former USSR countries may contain 200,000 of these disposal sites. Western Europe, North America and other developed have made a concerted effort to identify and define their waste disposal sites, and are actively remediating them. 

Woodland Township, NJ Weldon Spring Quarry, St. Charles City, MO Monticello Radioactivity-Contaminated Properties, Monticello, UT Uravan Uranium Project, Montrose City, CO. Disposal of incandescent lights and lanterns containing thorium-232 will be an additional source of thorium at waste disposal sites. 

Because you are more interested in groundwater contamination, you wonder how fast TMP would be transformed by chemical reactions at 10°C and pH 8.0 in a leachate from a waste disposal site containing 0.25 M Cl, 0.05 M Br", and 10-4 M CbT. Calculate the approximate half-life of TMP under these conditions by trusting your colleague s measurements and by assuming that all relevant reactions exhibit about the same activation energy of 95 kJ-mol"1. Also assume an s-value of 0.9 in the Swain-Scott relationship (Eq. 13-3). 

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