Remediation process

Debris with particularly good absorbent qualities such as wood, some paper products, paper, cloth materials, etc., are go candidates for shredding so that they can be included in the remediation process. Materials that are not porous and are not adsorbent are glass, plastic, metal objects, some types of construction debris, tanks, etc., are good candidates for manual or magnetic separation. 

Gatliff, E.G., Vegetative remediation processes offers advantages over traditional pump-and-treat technologies, Remediation, 4, 343-352, 1994. 

Remediation processes to deal with atmospheric emissions include ... 

A second recommendation is to complete LCI databases with data on additives. Both production data of additives and emission data of additives from compound materials in the use and waste phase are missing and should be supplemented. An important role in this data remediation process should be played by industry. 

Cr(VI).Other remediation processes for Cr(VI) contaminated soils include H2S injection, aqueous Fe(II) injection, and the use of reduced Fe solids. Aqueous-phase Cr(VI)-Fe(II) redox reactions may be significant if Fe2+ concentrations are in equilibrium with relatively soluble, ferric hydroxide-like phases (Tokunaga et al., 2003). The overall interactions involving microbial activity, organic carbon degradation, Fe2+, and mineral surfaces control the net rates of Cr(VI) reactions in soils. 

Processes reported in Table 1 have been carried out at temperature ranging, typically, between 20 and 40°C. Though the investigations carried out at lower temperature are very few [26, 33], this issue holds a key role in the design and optimization of the conversion processes. Provided that the heating-up of the waste-water streams is not economically feasible, the remediation process should be carried out at low temperature, particularly pressing in rigorous climate countries [50]. 

Once a bioremediation effort is started, the bioreactions that occur in the presence of added electron acceptors will result in significant variations of water chemistry across the three-dimensional area of the aquifer. Careful monitoring of these variations is an important indicator of the effectiveness of the remediation process. 

Ideally, the site characterization study has defined the vertical and horizontal extent of the contamination. Contoured site maps showing the (three-dimensional) distribution of the contaminants allow identification of areas that require extensive restoration, or may be allowed to be monitored to closure under natural attenuation. Knowledge of how much contamination exists and its location is the important first step in the remediation process. Evaluation of these data will permit consideration of the various remediation remedies available. Where the contaminant is contained within the shallow (<6 m) unsaturated zone and is recalcitrant (not readily biodegradable), excavation for off-site treatment or disposal may be the most expeditious procedure. Alternatively, depending on the contaminant, a variety of in situ procedures, including bioremediation, air sparging, soil vapor extraction, and fixation, may be applicable. 

Clausen, C.A. (2004a). Inproving the two-step remediation process for CCA-treated wood part I. Evaluating oxalic acid extraction. Waste Management, 24(4), 401-405. 

Table 2 is a slightly different view of the applicability of the remediation process. It is broadly divided into organic and inorganic contaminants, and considers the ease of applying a specific technology to a soil type. The categories and assumptions in Table 2 are very broad, and... 

The identification of faults and drawbacks in the remediation process, as well as of strengths and advantages of these processes... 

Phytoremediation is the use of plants to treat or stabilize contaminated soils, sediments, or water. Plants provide and support remediation processes in many ways. Common applications of phytoremediation-based systems include remediation of contaminated soil and groundwater, reuse of municipal wastewater and biosolids, reuse of industrial wastewater and by-products, alternative landfill capping and erosion control, and landfill leachate reuse. 

Dowex Optipore is a polymeric adsorbent used to treat chlorinated volatile organic compound (CVOC) contaminated off-gas streams from remediation processes such as air stripping of groundwater and soil vapor extraction. According to the vendor Dowex Optipore adsorbent has the following advantages over activated carbon ... 

Heterogeneities or anomalies in the soil will reduce removal efficiencies. Extreme pHs at the electrodes may inhibit the system s effectiveness. The electrokinetic remediation process is limited by the solubility of the contaminant, the desorption of the contaminants from the soil matrix, and reduction-oxidation changes induced by the electrode reactors. Electrokinetic remediation requires sufficient pore water to transmit the electrical charge. Contaminant and noncontaminant concentrations effect the efficiency of the process. 

SOLFIX is an ex situ stabilization technology that treats heavy metals by reacting contaminated soils and sediments with cement, pozzolanic materials, and other additives to chemically immobilize contaminants into an insoluble form. SOLFIX can be used either as a stand-alone technology or it can be incorporated with Hydro-SEP (a sediment washing technology) and ORG-X (a solvent extraction technology) into a three-step remediation process termed integrated sediment decontamination system (ISDS). 

In 1992 the vendor claimed that high-volume treatment, solids removal, and continuous chemical monitoring can be incorporated into a turnkey on-site remediation process with total costs as low as 1.00/1000 gal of waste treated (D16027A, p. 800). 

The Terra Vac heap leaching technology is an ex situ hazardous remediation process that has been previously applied by the mining industry to recover gold, uranium, copper, and other... 

R. E. Hinchee, R. M. Miller, and P. C. Johnson, eds., In situ Aeration Air Sparging Bioventing and Related Remediation Processes, Battelle Press, Columbus, Ohio, 1995. 

According to treatment mechanisms, however, treatment technologies are classified as biological, physicochemical, and thermal processes. In terms of the place where the actual treatment takes place, the issue of in situ vs. ex situ comes into play as far as selecting the most cost-effective remediation processes. For example, most bioremediation processes are in situ, while physicochemical processes may be implemented both in situ and ex situ, according to the following ... 

---