Soil recovery

If the remedial action involves the treatment of contaminated water (such as pump-treatment for groundwater recovery or soil-washing for soil recovery, which will be discussed in Section 18.8.2), then the preliminarily recovered water can be combined with a treatment stream for further... 

Farrington et al. [346] developed a high-performance liquid chromatographic method to perform positive monitoring down to 200 xg/kg of chlor-bromuron, chlorotoluron, diuron, linuron, monolinuron, chloroxuron, mono-uron and metobromuron in methanolic extracts of soils. Recoveries were in the range 97.5 to 102%. 

It was reported that the recoveries of 17 PAHs from six certified reference marine sediments and soils [77] increased from 70 to 75% when the temperature was increased from 50° C to 115°C, and remained at 75% from 115 to 145°C. In the extraction of OCPs from sediments, recovery was unchanged from 100 to 120°C [74]. In the extraction of phenylurea herbicides from soils, the recovery peaked in the range 60 to 80°C and decreased at lower or higher temperatures [75]. In the extraction of sulfonylurea herbicides from soils, recovery dropped from 70 to 80% to 1 to 30%. due to decomposition when temperature increased from 70°C to 115°C [79]. The recovery of oligomers from poly(ethyleneterephthalate) increased as temperature rose... 

Female Sprague-Dawley rats were exposed dermally to H]-benzo[a]pyrene (1 ppm) containing petroleum crude oil alone or in fortified soil matrix for 4 days (Yang et al. 1989). Recovery of radioactivity was 35.3% of the dose applied in oil, as follows urine (5.3% of dose), feces (27.5%), and tissues (2.5%) 96 hours after beginning of exposure. Recovery was 9.2% of applied dose with benzo[a]pyrene from petroleum crude-fortified soil recoveries in urine, feces, and tissues were 1.9%, 5.8%, and 1.5%, res 3ectively, at 96 hours. Benzo[a]pyrene (10 ppm) with acetone vehicle or in soil was applied to a 12 cm area of abdominal skin of female rhesus monkeys for 24 hours (Wester et al. 1990). Urine contained 51 22% of the dose with acetone vehicle and 13.2 3.4% with soil. 

Product Type in Hydraulic Interceptor Soil Soil Recovery... 

EIA and GC results were compared for the analysis of simazine in soil, using ethyl acetate for extraction of dried samples of sandy loam from a site contaminated by an experimental simazine spill. For 24 samples that had simazine content between 0 and 350 ppb by GC analysis, the results by EIA correlated with r = 0.93 and a slope of 1.26 (Figure 6). For an extended data set of 48 samples containing simazine from 0 to 3 ppm, the correlation between EIA and GC determinations was 0.97, with a slope of 0.81 (A. Lucas, unpublished data). To ensure solubilization of the simazine recovered from the most heavily contaminated samples, methanol was added to the PBS>Tween to 5% (v/v) as coeolvent. Atrazine residues were recovered by extraction with 90% acetonitrile and concentration on SCX solid phase columns. For samples spiked with 10, 25, 50, and 100 ppb (ng atrazine per gram of soil) recoveries of 80%, 82%, 79%, and 93%, respectively, were obtained. 

Period (Year) "CO, evolmF "c vtdaHUze

rice plants (exceptfor rooO "c leadted Cin soil Recovery... 

Microbial leaching of metals from ores is a promising adjunct to more aggressive metal recovery technologies (77), but is generally achieved by oxidative processes that generate very acidic waters. It seems unlikely that similar approaches will be of much value in removing contaminant metals and metalloids from soils. 

As the economic value of coproducts has decreased, it has become more difficult to provide capital for environmental controls on air emissions and wastewater streams such as toxic phenoHc effluents from chemical recovery operations. Some former coke and manufactured gas sites may require remediation to clean up contaminated soil and groundwater. These difficulties will force the shutdown of some operations and discourage recovery of coproducts in future installations. 

A multiresidue analytical method based on sohd-phase extraction enrichment combined with ce has been reported to isolate, recover, and quantitate three sulfonylurea herbicides (chlorsulfuron, chlorimuron, and metasulfuron) from soil samples (105). Optimi2ation for ce separation was achieved using an overlapping resolution map scheme. The recovery of each herbicide was >80% and the limit of detection was 10 ppb (see Soil chemistry of pesticides). 

By-Products. The biomass from the fungal fermentation process is called mycellium and can be used as a supplement for animal feed since it contains digestable nutrients (25,26). The lime-sulfuric purification and recovery process results in large quantities of calcium sulfate cake, which is usually disposed of into a landfill but can find limited use in making plaster, cement, waUboard, or as an agricultural soil conditioner. The Hquid extraction purification and recovery process has the advantage of Htde soHd by-products. 

The influence of soil ageing on the recovery of POPs from spiked soil samples was also assessed. Spiked lettuce samples were subjected to in vitro gastrointestinal extraction to assess the bioavailability of Endosulfan compounds. All samples (soil and lettuce) were extracted using pressurised fluid extraction and analysed using gas chromatography with mass selective detection. 

The best overall recovery of labelled fertilizer in crop and soil was 99% and the leastsatisfactory 65%. Thus 1-35% ofthe labelled nitrogen, onaverage 15.7%, was missing, presumed lost . These losses occurred between the time of the fertilizer application in spring and the time the crop was harvested but why and how did they occur ... 

The atmospheric movement of pollutants from sources to receptors is only one form of translocation. A second one involves our attempt to control air pollutants at the source. The control of parhculate matter by wet or dry scrubbing techniques 3delds large quantities of waste materials—often toxic—which are subsequently taken to landfills. If these wastes are not properly stored, they can be released to soil or water systems. The prime examples involve the disposal of toxic materials in dump sites or landfills. The Resource Conservation and Recovery Act of 1976 and subsequent revisions are examples of legislation to ensure proper management of solid waste disposal and to minimize damage to areas near landfills (4). 

The most commonly used remediation technique for the recovery of organic contaminants from ground water has been pump- and-treat, which recovers contaminants dissolved in the aqueous phase. In this regard, the application of carbon adsorption has found extensive, but not exclusive use. Vacuum extraction (also called soil venting) has also become popular for removal of volatile organic contaminants from the unsaturated zone in the gaseous phase. Both of these techniques can, in the initial remediation phase, rapidly recover contaminants at concentrations approximately equal to the solubility limit (pump-and-treat), or the maximum gas phase concentration of the contaminant (vacuum extraction). The... 

The Brio refining site is approximately 58 acres in size and is the location of a former chemical production, recovery, refinery, and regeneration facility. The site includes closed impoundments into which hazardous substances were disposed in bulk, storage tanks, and approximately 1,750 drums of hazardous substances. Remediation activities included the excavation and incineration of contaminated soil, installation of protective liners around selected pits, and the installation of a groundwater extraction system adjacent to a gully. 

Petroleum Enhancing oil recovery, regulation of filterability and rheological properties of drilling muds, thickening of water, soil structure formation, oil flotation... 

Interest in the chemistry of water-soluble polymers (polyelectrolytes) has been continually increasing during the past 45 years. The tremendous scope of utility for water-soluble polymers has led to a vigorous search for new materials and the rapid development of polyelectrolytes into a dynamic field of industrial research. Growth in this field has been especially rapid since 1960 and today, many companies are engaged in synthesis and applications research on polyelectrolytes that are primarily used in four main marketing areas water treatment, paper, textiles, and oil recovery [1]. Polyacrylamide gel was also used as soil conditioner [2-4]. 

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