Site-specific monitoring

In many countries, both programmes measure the environmental radiation field and radioactivity in air, water and the various elements of the food chain the objective is to enable continuous assessments to be made of the impact of radioactivity on health, and on the environment. In some countries, the two programmes are complementary so that country-wide monitoring provides an independent check on site-specific monitoring. 

Compile chronic toxicity data -dissolved metal (pg Me/L) Compile site-specific monitoring data -dissolved metal (pg Me/L)... 

Site-specific monitoring concept monitoring has to gauge effectiveness and demonstrate that NA is occurring as expected contingency measures have to be provided for such case that NA fails to perform as predicted and performance criteria cannot be met. 

Quantitative measurement of contaminants in the environment is complex and costly for substances like dioxin, which consist of a number of different isomers at very low detection levels. Therefore, such empirical, detailed, site specific monitoring data cannot be gathered independently for each body of water. Models developed based upon available data provide a theoretical framework for understanding the movement of chemicals in the environment and for developing principles to assess contributions of major sources to a given waterbody. 

A number of site-specific factors must first be evaluated. Including (1) the chemical characteristics and amount of hazardous waste, (2) the potential for release to the environment, (3) the sensitivity of the particular environment to the hazardous waste, (4) the proximity of the hazardous waste to humans, and (5) Its potential effect on human health. Then the environmental engineer must decide If a field Investigation of the site Is necessary, whether a feasibility study for remedial action Is required, what remedial action Is required to mitigate. If not eliminate, the contamination, and finally, what monitoring plan will enable the efficacy of the remedial action to be evaluated. 

U.S. EPA defines MNA as the reliance on natural processes, within the context of a carefully controlled and monitored site cleanup approach, to achieve site-specific remediation objectives within a time frame that is reasonable compared to that offered by other more active methods. The natural processes include biodegradation, dispersion, dilution, sorption, volatilization, stabilization, and transformation. These processes reduce site risk by transforming contaminants to less toxic forms, reducing contaminant concentrations, and reducing contaminant mobility and bioavailability. Other terms for natural attenuation in the literature include intrinsic remediation, intrinsic bio-remediation, passive bioremediation natural recovery, and natural assimilation. 30... 

At this point it is important to note that the flow model (a hydrologic cycle model) can be absent from the overall model. In this case the user has to input to the solute module [i.e., equation (1)] the temporal (t) and spatial (x,y,z) resolution of both the flow (i.e., soil moisture) velocity (v) and the soil moisture content (0) of the soil matrix. This approach is employed by Enfield et al. (12) and other researchers. If the flow (moisture) module is not absent from the model formulation (e.g., 14). then the users are concerned with input parameters, that may be frequently difficult to obtain. The approach to be undertaken depends on site specificity and available monitoring data. 

The placement of injection (or injection galleries), extraction, and monitoring wells is very site specific depending on the local site and subsurface conditions. The essential criteria for locating these units are as follows ... 

IV 100- 300 Sites requiring specific monitoring on particular waste piles, discharges or stream sediments on a five yearly basis. 

The analytical procedures for Level 3 are specific to selected components identified by Level 2 analysis and are oriented toward determining the time variation in the concentrations of key indicator materials. In general, the analysis will be optimized to a specific set of stream conditions and will therefore not be as complex or expensive as the Level 2 methods. Both manual and instrumental techniques may be used, provided they can be implemented at the process site. Continuous monitors for selected pollutants should be incorporated in the analysis program as an aid in interpreting the data acquired through manual techniques. The total Level 3 analysis program should also include the use of Level 2 analysis at selected intervals as a check on the validity of the key indicator materials which reflect process variability. 

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