Monitoring- networks/sites

Figure 2.3.3 Monitoring network site selection matrix...

TCDD was detected more frequently in background fish samples. EPA estimates that 21 percent of the USGS national national monitoring network sites have detectable levels. 

A number of medium- to long-term enviromnental monitoring networks and programs have been developed over the past 4 decades in the United States, all of which have had to deal with network design issues noted here. Some of these efforts are summarized in Table 5.3. As indicated in Table 5.3, some programs have emphasized random or partially random designs, whereas others have utilized nonrandom designs but based on specific site criteria. 

Remediation optimization uses defined approaches to improve the effectiveness and efficiency with which an environmental remedy reaches its stated goals. Optimization approaches might include third-party site-wide optimization evaluations conducted by expert teams, the use of mathematical tools to determine optimal operating parameters or monitoring networks, or the consideration of emerging technologies. Since 1999, U.S. EPA has promoted remediation optimization in the following manner ... 

Monitoring of the composition of rain water in Switzerland began in 1985 at five different sites in the frame of the National Air Pollution Monitoring Network [24]. In Table 1 average concentrations of sulfate, nitrate, and ammonium at the site... 

During the field demonstration in 1997 at the Department of Defense s (DOD s) Operable Unit 2, Hill Air Force Base in Utah, approximately 908 gal of dense, non-aqueous-phase liquids (DNAPLs) were removed from contaminated soils. The cost of the demonstration was 230/yd of soil treated and 165/gal of DNAPL removed. These costs included the purchase of all the equipment and an extensive monitoring network. It is estimated that future applications at the site would require roughly half as many wells and the boiler rental would be restricted to a much shorter period. These conditions would lower the direct treatment costs to 103/yd of treated soil and 74/gal DNAPL removed (D18518W, p. 216). 

The CASTNET provides atmospheric data on the dry deposition component of total acid deposition, ground-level ozone, and other forms of atmospheric pollution. CASTNET is considered the nation s primary source for atmospheric data to estimate dry acidic deposition and to provide data on rural ozone levels. Used in conjunction with other national monitoring networks, CASTNET is used to determine the effectiveness of national emission control programs. Established in 1987, CASTNET now comprises over 70 monitoring stations across the United States. The longest data records are primarily at eastern sites. The majority of the monitoring stations are operated by EPA s Office of Air and Radiation however, approximately 20 stations arc operated by the National Park Service in cooperation with EPA. 

The monitoring network in EMB compared to those established in Central and North Europe or even with the Western Mediterranean Basin (e.g. Spain) is rather insufficient. Particularly there is a lack of data on continuous or long-term monitoring of the chemical composition of particulate matter [12], For some substances (e.g. carbonaceous aerosol), the variability is expected to be much larger than can be resolved by integrating the available measurements and the research studies need to be supported by assessment of the local scale variability. In order to understand the temporal evolution (trends) there is also a particular need for aerosol measurements at additional sites with little influence from local and regional emission sources. 

Cortes et al. [33] report that gas-phase concentrations of PAHs have been steadily decreasing at all sites since the inception of this extensive monitoring network. Interestingly, particle phase PAHs do not exhibit the same decreasing trend. All but one location (Sleeping Bear Dunes, MI) show no decrease in particle phase concentration over the same period from 1991 through 1999. 

The EMEP monitoring network of precipitation chemistry consists of about a hundred stations distributed in almost 30 countries across Europe.1 All of these measure inorganic ions as well as pH and conductivity. Figure 17.1 illustrates the concentration levels of sulfate (corrected for sea salt), nitrate, and ammonium in 2006. The monitoring sites of heavy metals and persistent organic pollutants (POPs) are less densely distributed 2 in 2006, there were around 50 for heavy metals such as lead... 

An extensive multi-year monitoring program for CDDs/CDFs was conducted at eight sampling locations in the Los Angeles South Coast Air Basin from 1987 to 1989 (Hunt and Maisel 1992). The monitoring network, which monitored for both vapor and particulates, included several sites situated in residential... 

Previously published data from two sites on the Wisconsin Acid Deposition Monitoring Network (2) and the University of Virginia site of the MAP3S Precipitation Chemistry Network (PCN) (3, 8) were used in the current study. The Wisconsin data were obtained for samples collected during the spring of 1984, and the Virginia data were related to selected samples analyzed during the summer of 1983. 

Several nationwide monitoring networks in the U.S. collect data that can be used to estimate N deposition. These include the NCDC for precipitation, NADP for precipitation chemistry and the Clean Air Status and Trends Network (CASTNet) for dry deposition. Few of these sites are in coastal systems, however, so caution must be taken when using these data. 

Evans C. D., Monteith D. T., and Harriman R. (2001c) Longterm variability in the deposition of marine ions at west coast sites in the UK acid waters monitoring network impacts on surface water chemistry and significance for trend determination. Sci. Tot. Environ. 265, 115-129. 

SMETs are tools and methods that are expected to provide better suited information within the WFD monitoring networks either in combination with classical techniques, or directly replacing them in their capacity e.g. to confirm the presence of certain compounds without tedious work required (semi-quantitative methods), to allow frequent monitoring (online systems) or to provide more representative data (passive samplers), and to provide data directly on-site (kits). 

This currently operating network extends from Alaska to Puerto Rico, and from Maine to American Samoa with 190 sampling sites. Many of the stations have been identified as National Trends Network (NTN) sites - the monitoring network of the National Acid Precipitation Assessment Program (NAPAP) (15). 

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