Hazardous waste results

Data shown in Table II consists of materials which can contribute to salinity, toxic elements had not been considered. More recently, the U. S. Environmental Protection Agency has proposed an extraction procedure to determine hazardous wastes. Results obtained using the proposed EPA extraction procedure are shown in Table III for Paraho retorted shale. The low... 

Federal regulations (40 CFR 261) classify acrylonitrile as a hazardous waste and it is Hsted as Hazardous Waste Number U009. Disposal must be in accordance with federal (40 CFR 262, 263, 264), state, and local regulations only at properly permitted faciUties. It is Hsted as a toxic pollutant (40 CFR 122.21) and introduction into process streams, storm water, or waste water systems is in violation of federal law. Strict guidelines exist for clean-up and notification of leaks and spills. Federal notification regulations require that spills or leaks in excess of 100 lb (45.5 kg) be reported to the National Response Center. Substantial criminal and civil penalties can result from failure to report such discharges into the environment. 

Solid and Hazardous Waste. Regulation of pollution resulting from soHd waste disposal was formulated at a much slower pace than regulation of air or water pollution. It was not until the Resource Conservation and Recovery Act (RCRA) of 1976 (6) was passed that substantial controls were authorized. 

A sohd waste is considered hazardous if it is either a Hsted waste or a characteristic waste. Listed wastes include a Hst of specific processes that generate a waste and a Hst of discarded commercial chemical products. There are four hazardous waste characteristics ignitabiHty, corrosivity, reactivity, and toxicity. The last refers to the leachabiHty of a waste and the resultant toxicity in the groundwater using the analytical method referred to as toxicity characteristic leaching procedure (TCLP). A Hst of substances included under TCLP is shown in Table 1. 

Transportation and Disposal. Only highly alkaline forms of soluble sihcates are regulated by the U.S. Department of Transportation (DOT) as hazardous materials for transportation. When discarded, these ate classified as hazardous waste under the Resource Conservation and Recovery Act (RCRA). Typical members of this class are sodium sihcate solutions having sihca-to-alkah ratios of less than 1.6 and sodium sihcate powders with ratios of less than 1.0. In the recommended treatment and disposal method, the soluble sihcates are neutralized with aqueous acid (6 Af or equivalent), and the resulting sihca gel is disposed of according to local, state, and federal regulations. The neutral hquid, a salt solution, can be flushed iato sewer systems (86). 

Small lab-pack containers of hazardous waste if they are first placed in nonlealdug, larger containers. These containers must be Filled to capacity and surrounded by enough absorbent material to contain the liquid contents of the lab pack. The resultant container must then be placed in a larger container packed with absorbent material which will not react with, become decomposed by, or ignited by the contents of the inside containers. Incompatible wastes may not be packed and disposed of together in this manner. 

HAZWOPER applies only where exposure to hazardous substanees or to health and safety hazards resulting from a hazardous waste operation is likely (see Eigure 2-1). This ean be determined by analysis of exposure monitoring data, hazard eharaeterization, hazard analysis, or exposure assessment [1]. Some of the speeifle examples of work aetivi-ties and situations will be eovered later. 

Safety hazards are treated in the same manner. For example, workers who work in trenches in clean areas of the site would be covered by the OSHA Excavation and Trenching Standard, Subpart P, 29 CFR 1926. Workers who work in trenches in contaminated areas would fall under both Subpart P and HAZWOPER. Workers who do not work in trenches fall under HAZWOPER only when working in contaminated areas and would not be covered by either standard when working solely in clean areas, provided they are not exposed to safety hazards resulting from hazardous waste operations. 

HAZWOPER does not eover elerieal or support personnel, workers at the perimeter of a hazardous waste worksite, or workers engaged in eonstruetion aetivities in uneontaminated areas, provided they are not exposed, or have possibly been exposed, to hazards resulting from the operations. These workers would fall under the seope of other appropriate standards of praetiee that are more proteetive of health and safety [11-... 

Only qualified individuals should be allowed to develop air monitoring strategies. In addition, only trained and qualified field personnel should operate sereening equipment and be allowed to interpret results. For many sites, the results obtained from direet reading instruments ean help determine a variety of important faetors on a hazardous waste site. These faetors inelude ... 

Nonemergency medical care should be arranged for hazardous waste site personnel who are experiencing health effects resulting from an exposure to hazardous substances. Off-site medical care should make sure that any potential job-related symptoms or illnesses are evaluated in the context of the employee s exposure. Off-site medical personnel should investigate and treat non-job-related illnesses that may put the employee at risk because of task requirements [1]. 

PBPK models improve the pharmacokinetic extrapolations used in risk assessments that identify the maximal (i.e., the safe) levels for human exposure to chemical substances (Andersen and Krishnan 1994). PBPK models provide a scientifically sound means to predict the target tissue dose of chemicals in humans who are exposed to environmental levels (for example, levels that might occur at hazardous waste sites) based on the results of studies where doses were higher or were administered in different species. Figure 3-4 shows a conceptualized representation of a PBPK model. 

Methyl parathion has been released to the environment mainly as a result of its use as an insecticide on crops. It is applied to agricultural crops by aerial or ground spraying equipment. Methyl parathion has been detected in surface waters and sediments, rainwater, aquatic organisms, and food. There are no known natural sources of the compound. Methyl parathion has been identified in at least 16 of the 1,585 hazardous waste sites on the NPL (HazDat 2001). 

Exposure of the general population to higher concentrations of methyl parathion may result from contact with, or ingestion of, contaminated hazardous waste site media, principally soils and water. No information was found in the available literature regarding the size of the human population potentially exposed to methyl parathion through contact with contaminated waste site media. 

However, a sample taken in the doctor s office can be properly packed and shipped to a special laboratory, if necessary. Because endosulfan leaves the body fairly quickly, these methods are useful only for finding exposures that have occurred within the last few days. At this time, these methods can only be used to prove that a person has been exposed to endosulfan. The test results cannot be used to predict if you wiU have any adverse health effects. Exposure to other chemicals at the same time at hazardous waste sites could cause some confusion in understanding these results. More information about tests to find endosulfan in the body is presented in Chapters 2 and 6. 

Anand et al. 1987). The authors hypothesized that the ocular effects associated with endosulfan may be a result of prolonged hypertension (although no data on blood pressure were presented, and there is no other information to indicate that chronically administered endosulfan induces hypertension) or an endosulfan-induced vitamin A deficiency (which was observed in this study). Although the rabbit may represent a uniquely sensitive species, the possibility that long-term exposure of persons at hazardous waste sites to endosulfan may result in adverse effects on ocular tissues cannot be eliminated. 

Agarwal et al. 1978), the quantification of these specific enzymes may indicate that exposure to endosulfan has occurred. Blood tests, such as decay curves for aminopyrine in plasma, which are semiquantitative indices of liver enzyme induction, have been used successfully in the past to demonstrate enzyme induction in pesticide-exposed workers. Because numerous chemicals found at hazardous waste sites also induce these hepatic enzymes, these measurements are not specific for endosulfan exposure. However, measurements of enzyme activity, together with the detection of the parent compound or its metabolites in tissue or excreta, can be useful indicators of exposure. All of these potential biomarkers require further verification in epidemiological studies. Further studies with focus on the development of methods to separate and measure the estrogenicity of endosulfan in in vitro assays would be valuable since these assays are more sensitive and discriminative than other conventional biomarkers. Preliminary results have been presented by Sonnenschein et al. (1995). 

Production, Import/Export, Use, Release, and Disposal. Endosulfan is distributed in the environment as a result of its use as an insecticide (Gregor and Gummer 1989 NRCC 1975 Strachan et al. 1980). Humans may be exposed through the ingestion or use of contaminated food (Gartrell et al. 1986 Podrebarac 1984a) or tobacco products (EPA 1982a), contact with media from contaminated hazardous waste sites (principally soils), or insecticide apphcafion (Oudbier et al. 1974 Wolfe et al. 1972). 

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