GENERIC SITE CHARACTERISTICS

Regional climate should be the first consideration when evaluating the suitability of an alternative landfill cover for a site. If the regional climate appears to be compatible with the requirements of the alternative cover, then site characteristics should be examined to determine whether the site climate is also suitable. Site and regional climate may differ substantially for sites near mountains, in valleys, in the rain shadow of coastal mountains, or near the coast. The Air Force Center for Environmental Excellence commissioned a generic assessment of the suitability of the ET landfill cover based on regional climate for the continental United States.4... 

The Environment Report provides a summary of all the environmental and waste management assessment undertaken to support APIOOO build in the UK. The Environment Report refers to a generic site, details of which are provided in UKP-GW-GL-025, Characteristics of a Generic Site for a Nuclear Power Station (Reference 14.5) and which is discussed further in Chapter 3 of this PCSR. A similar approach will be taken to develop this report to reflect the features of a future real site. 

A description of the key regulations with which the APIOOO will demonstrate compliance are described below, together with a description of the main characteristics of the generic site. 

Generic rules are based on the QSAR equations and their coefficients. Forward chaining using these rules yields basic characteristics for the receptor site model. For instance, an abstracted generic rule may take the form ... 

The extent of reaction (or conversion) at any stage can be expressed by the fraction of total reactive sites that have been consumed. Reactive sites usually display the same reactivity regardless of the size of the molecule to which they are linked. The polymerization process has the characteristics of a statistical combination of fragments. In this way, a distribution of products from the monomer to a generic n-mer is obtained (Table 2.1), with average molar masses increasing continuously with conversion. 

A risk-based waste classification system must focus on the inherent characteristics of waste, representative facilities, and generic events, because the system necessarily presumes that specific disposal sites and related waste treatment and disposal technologies have not yet been identified and characterized. NCRP emphasizes that the principles, framework, and implementation details of a risk-based waste classification system do not provide a substitute for site-specific risk assessments. The two most important cases where site-specific risk must be estimated are (1) an assessment of risk for the spectrum of actual wastes at a specific disposal site for the purpose of establishing site-specific waste acceptance criteria, and (2) an assessment of risk posed by a prior waste disposal at a site for the purpose of determining whether the risk is unacceptable and, thus, whether remedial action is required at the site. 

Describe the conditions of waste disposal. Wastes in specified physical and chemical forms and having certain compositions or ranges of compositions of hazardous substances are assumed to be emplaced in certain ways in a disposal site having specified characteristics. The disposal site can be a real location or generic with hypothetical characteristics typical of real sites. The exposure assessment usually assumes that disposal operations have been completed and the site is closed, although the... 

In classifying waste based on considerations of risks resulting from disposal, hypothetical and generic disposal sites or abstractions of real sites must be considered, because waste may be classified before disposal sites are chosen and multiple disposal sites may be used for similar wastes. An important characteristic of waste disposal systems is that risks resulting from release of hazardous substances and transport beyond the site boundary are highly site-specific,... 

The use of the characteristic functions facilitated the extension of the stochastic theory to two-site [99] or to generic multiple-site heterogeneous surfaces [100] that are very complex to handle otherwise [5,101,102]. Thus, the stochastic theory is able to model the band profiles that are due to any unimodal or multimodal distribution of adsorption energies. The stochastic model was further extended to describe the effect of mobile phase dispersion and size exclusion effects as well [7,8,103]. 

The variations in diversity and function between individual natural ecosystems are too large to allow a broad-brush generic approach to receptor response and some form of site-specific estimation is normally needed. However, the methodology for this is not fully developed at this time. The characteristics of ecosystems that are important to describe and to assess in terms of receptor response are not agreed. Among the proposed approaches11 is a focus on the contaminant... 

The overall risk estimation should cover all the pollutant linkages identified, broken into site zones as appropriate. Details should be provided of source concentrations, with estimated confidence limits, the receptor characteristics and confirmation of the viability of the pollutant pathway. If generic guideline values are used, then their applicability should be supported. Clearly, full details need to be recorded of any models and data used to generate site-specific values for unacceptable risk, together with a commentary on assumptions that have been made in their application. 

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