Surface water contamination

Insecticide methomyl is a very toxic pesticide and is highly soluble in water (57.9 g/1). It has a low sorption affinity to soil and can cause groundwater and surface water contamination in agricultural areas. Solubilities of methomyl in different solvents are in methanol 1000 g/1, in aceton 730 g/1, in ethanol 420 g/1, in isopropanol 220 g/1, in toluene 30 g/1. 

Important intermedia transfer mechanisms that must be considered where significant surface water contamination is expected include transfers to ground water where hydrogeology of the area indicates significant surface water-ground water exchange, transfers to biota where waters contaminated with lipophilic substances support edible biotic species, and transfer... 

In extreme situations, incompatibility between injection fluids and reservoir components can be so great that deep-well disposal will not be the most cost-effective approach to waste disposal. In other situations, such remedial measures as pretreatment or controlling fluid concentrations or temperatures can permit injection even when incompatibilities exist. In addition to operational problems, waste-reservoir incompatibility can cause wastes to migrate out of the injection zone (casing/confining-layer failure) and even cause surface-water contamination (well blowout). 

Micro-Flo has been used at many sites throughout Canada to treat wastewater and surface water contaminated with polychlorinated biphenyls (PCBs), chlorophenols, polycyclic aromatic hydrocarbons (PAHs), phenols, dioxins, furans, hydrocarbons, metals, oil, and grease. The technology has also been used to treat water contaminated with paint, paint thinner, and paint solvents. 

Allen, J. M., S. Lucas, and S. K. Allen, Formation of hydroxyl radical in illuminated surface waters contaminated with acidic mine drainage , Environ. Tox. Chem., 15,107-113 (1996). 

NAPIAP. (1992). The Effects of Restricting or Banning Atrazine Use to Reduce Surface Water Contamination in the Upper Mississippi River Basin A Summary. Washington, D.C. NAPIAP, USDA. 

Composite data from the Comprehensive Emergency Response, Compensation, and Liability Act (CERCLA) monitoring program indicate that benzene was detected at a frequency of 11.2% in groundwater in the vicinity of 178 inactive hazardous waste disposal sites (Plumb 1987). Data from a 1980 national survey by the Council on Environmental Quality on groundwater and surface water contamination showed benzene concentrations in contaminated drinking water wells in New York, New... 

Project development The development of a mining site and supporting infrastructure causes extensive land clearance. Also, groundwater and surface water contamination can be caused by spills and leaks from fuel storage tanks, and from waste disposal. 

Industrial contamination of water occurs as the result of directly introducing contaminated wastewater into a body of water or lake or from improper disposal of chemicals to the land. The chemicals most frequently found in water from both of these activities are chemicals that are used in very high volume or are very mobile. The nature of surface waters contamination is more likely to depend on the... 

Surface Water Pathway. The surface water pathway of DPM rates the potential for contaminants from a waste site to enter surface waters via overland flow routes, or from ground water discharge to surface water. If pollutants are not directly observed in surface water, but are present in sediments or soil, there is a potential for surface water contamination so it is necessary to collect information from which their likelihood to reach a receptor can be estimated. The following variables are scored to provide an indication of this exposure potential ... 

Capping the residue pile and closure of operation must be done in an environmentally safe manner. This also is an expensive proposition. Free cyanides are left in the residue may volatilize to the atmosphere or be destroyed by ultraviolet radiation. However, surface water contamination, even after the closure, becomes an important issue. Monitoring of groundwater wells installed at the time of closure is continued through the postclosure period, typically over a period of 30 years. It seems to be an important research task to develop processes that can be used for decisive treatment of residues and remediation of sites. 

Aqueous extracts. Various bioassay protocols are available for testing soil elutriates or leachates. Historically these have previously been available for aquatic tests. However, it may be inappropriate to project effects generated with aquatic species to soil organisms or ecosystems. With the development of whole soil bioassays, the use of elutriate or leachate tests focuses now on the prediction of threats to groundwater (leaching of toxicants) or surface water (contaminant run-off). Tests using aqueous extracts address pollutants soluble in water, and therefore are a measure of mobile toxicants. 

Data on pesticides residues in water for the period 1986-1990 indicated a trend of enhanced residues of DDT, but relatively lower concentrations of DDE (Figure 24.9). It is evident that these scattered and incomplete data for surface water contamination by chlororganic compounds are not sufficient to provide conclusions on the precise status of surface water in Lithuania. 

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