Site remediation, regulatory

This chapter presents a regulatory overview of on-site remediation, remedial investigations (RI), feasibility studies (FS), remedial technologies, and a simulated case study. The discussion of remedial investigations and feasibility studies also includes the development and selection of remedial technologies. The case study outlines a remedial investigation and feasibility study, as well as the selection of remedial technologies. 

In the selection of a microbial system and bioremediation method, some examination of the degradation pathway is necessary. At a minimum, the final degradation products must be tested for toxicity and other regulatory demands for closure. Recent advances in the study of microbial metabolism of xenobiotics have identified potentially toxic intermediate products (Singleton, 1994). A regulatory agency sets treatment objectives for site remediation, and process analysis must determine whether bioremediation can meet these site objectives. Specific treatment objectives for some individual compounds have been established. In other cases total petroleum hydrocarbons total benzene, toluene, ethyl benzene, and xylene (BTEX) or total polynuclear aromatics objectives are set, while in yet others, a toxicology risk assessment must be performed. 

Regulatory Approach to Site Remediation. Most environmental cleanup standards are derived from the provisions of CERCLA, section 121 "Cleanup Standards" or RCRA, Subtitle C entitled "Hazardous Waste Management." The implementing regulations are... 

Regulatory and U.S. Department of Energy Order Compliance—This section briefly describes those promulgated regulations, DOE orders, and consent order agreements between DOE, EPA, and Ecology that are considered applicable or relevant and appropriate requirements (ARAR) to the Hanford Site remediation and cleanup activities. 

Both removal and remedial actions may be carried out at the same site. To accomplish these tasks, CERCLA has given cleanup authority to U.S. EPA, has established the Hazardous Substance Response Trust Fund (Superfund) to finance the remedial actions at CERCLA sites, has initiated a procedure for the emergency response to accidental spills, and has imposed cleanup liability on those responsible. The National Contingency Plan (NCP) was developed in 1982 and in 1985 as the regulatory framework to guide these responses. 

The bioreactor landfill is a remedial alternative that can be applied either on site or off site. However, landfilling is regarded as the least attractive alternative at a site cleanup action. Landfilling of hazardous materials is becoming increasingly difficult and more expensive due to steadily growing regulatory control.92-93... 

The site-specific requirements for landfill remediation should be developed before beginning design or selection of cover type. Site-specific requirements depend on numerous site-specific factors, including landfill history waste type, quantity, and age climate geologic setting local surface water and groundwater use and regulatory requirements. 

The most cost-effective, technically feasible remediation procedures are not always in agreement with regulatory controls. Environmental regulations, by their very nature, must be applicable for a wide variety of settings and must protect the overall environment. In past years remediation standards were established as general numerical concentrations usually based on drinking water standards or other health-related criteria borrowed from related public health fields. This type of remediation was often generic, not site specific. 

Selection of approach or combination of approaches to LNAPL recovery and ultimately aquifer rehabilitation and restoration is dependent on numerous factors as discussed in the previous chapters. The case histories presented below reflect different remediation approaches and strategies in response to varying geologic and hydrogeologic conditions, site-specific constraints, and regulatory environment. A variety of LNAPL recovery systems are first discussed, including ... 

As already noted, the chemical composition of petroleum and petroleum products is complex and may change over time following release into the environment. These factors make it essential that the most appropriate analytical methods are selected from a comprehensive hst of methods and techniques that are used for the analysis of environmental samples (Dean, 1998 Miller, 2000 Budde, 2001 Sunahara et al., 2002 Nelson, 2003 Smith and Cresset, 2003). But once a method is selected, it may not be the ultimate answer to solving the problem of identification and, hence, behavior (Patnaik, 2004). There are a significant number of petroleum hydrocarbon-affected sites, and evaluation and remediation of these sites may be difficult because of the complexity of the issues (analytical, scientific, and regulatory not to mention economic) regarding water and soil affected. 

Currently, many regulatory agencies recommend the common methods (EPA 418.1, EPA 801.5 Modified) or similar methods for analysis dming remediation of contaminated sites. In reality, there is no standard for the measurement of total petroleum hydrocarbons since each method may need to be chosen or adapted on the basis of site specificity. 

End use is an important parameter because remediating JACADS to a residential standard typically would be more difficult than remediating the site to an industrial standard. The Army has favored an industrial standard, because the decision on which standard will be used and permitted by regulatory authorities may also set an important precedent for the closures (and costs) of other chemical agent disposal facilities. 

A UV/ozone Ultrox system was used to treat wastewater contaminated with phenol and polychlorophenol (PCP) at a wood processing facility in Denver, Colorado. The capital cost for the Ultrox system was 200,000. Operation and maintenance costs for the entire remediation system were 10.92 per 1000 gal of treated wastewater. This cost estimate excludes the expenses associated with site preparation, permitting and regulatory compliance, startup, analysis, effluent disposal, and demobilization (D205505, p. C-1). 

The treatment cost to remediate 20,000 tons of contaminated soil using a 10-tph VRU is estimated to be 137 per ton, if the system is online 90% of the time. Treatment costs increase as the online factor decreases. Projected unit costs for a smaller site (10,000 tons of contaminated soil) are 171 per ton projected unit costs for a larger site (200,000 tons) are 106 per ton for a 10-tph VRU and 72 per ton for a 100-tph VRU. These costs do not include site preparation, permits, regulatory requirements, monitoring, waste disposal, sampling and analysis, or posttreatment restoration, which are considered to be the obligation of the responsible party or site owner. Also not included in these estimates is profit on the part of the vendor (D10056R, pp. 16, 24). 

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