Remediation impoundment

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. 

The sources of contamination are usually those hazardous materials that are contained in drums, tanks, surface impoundments, waste piles, and landfills, as well as heavily contaminated media (such as soil) affected by the original leaking or spilling source. The purpose of defining sources of contamination is to help to identify the source location, potential releases, and engineering characteristics that are important in the evaluation of remedial actions, as well as waste characteristics, such as the type and quantity of contaminants that may be contained in or released to the environment, and the physical or chemical characteristics of the hazardous wastes present in the source. 

At another oil refinery in Eldorado, Arkansas, the technology treated 30,000 yd of impoundment sludge. STC Remediation, Inc., states that the reagent cost for this project was 8.00 per ton of treated waste (D113382, p. 19). 

Following on from the National Academies recommendations, it is necessary to demonstrate, on a site-by-site basis, that our understanding of the impoundment systems is good enough to create confidence in stakeholders that the approach being used to remediate the tailings is suitable for now and the long term. 

Kwong, Y.T.J. (2003) Characteristics of impounded tailings at Mount Nansen, Yukon territory implications for remediation, in Proceedings-Assessment and Remediation of Contaminated Sites in Arctic and Cold Climates, (eds M. Nahir, K. Biggar and G. Cotta), University of Alberta, Edmonton, pp. 57-62. 

Figure 14 Schematic diagram of a mine-waste impoundment with a combined remediation approach, including a cover to prevent O2 and water ingress, in situ mixing to geochemically stabilize waste, permeable reactive barrier in aquifer to treat subsurface drainage, and wetland for surface treatment of drainage.

Remedial investigation/feasibility studies being conducted at the 46 NPL sites where creosote has been found and at the numerous creosote-contaminated Resource Conservation and Recovery Act (RCRA) corrective action sites should provide data on concentrations of the mixture in contaminated media in the vicinity of hazardous waste sites. For example, creosote constituents have been found in surface water impoundments and soil samples taken near wood treatment facility sites in Colorado, Louisiana, Texas, and Montana. 

One of the major problems involved in the remediation of the Dioxin contaminated surface impoundment (lagoon) discussed earlier (1) was the treatment of the water to insure complete removal of any... 

During the 1970s and the early 1980s, toxic chemicals and other hazardous wastes were treated by land disposal or by incineration. The Hazardous and Solid Waste Amendments (HSWA) of 1984 to the Resource Conservation and Recovery Act (RCRA) severely restricted disposal of wastes in untreated landfills, surface impoundments, and land treatment units. Additionally, negative public opinion was focused on the disproportionate risk borne by those living near incinerators and other hazardous waste treatment and disposal facilities. Environmental laws passed in the 1970s clearly articulated public and congressional dissatisfaction with early site remedies that wholly consisted of containment, off-site disposal, and incineration. 

Table 8-3 presents the estimated cost for remediation of the 100-NR-l and lOO-NR-2 operable work units, which includes the remedial action and post-closure monitoring at the 1301-N LWDF, 1325-N LWDF, 1324-N surface impoundment, and 1324-NA percolation pond the RPP facilities at 100 N). 

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