MONITORING NETWORK

The U.S. Environmental Protection Agency has established National Ambient Air Quality Standards (NAAQS) for protection of human health and welfare. These standards are defined in terms of concentration and hme span for a specific pollutant for example, the NAAQS for carbon monoxide is 9 ppmV for 8 hr, not to be exceeded more than once per year. For a state or local government to establish compliance with a National Ambient Air Quality Standard, measurements of the actual air quality must be made. To obtain these measurements, state and local governments have established stationary monitoring networks with instrumentation complying with federal specifications, as discussed in Chapter 14. The results of these measurements determine whether a given location is violating the air quality standard. 

Stationary monitoring networks are also operated to determine the impact of new sources of emissions. As part of the environmental impact statement and Prevention of Significant Deterioration processes, the projected impact of a new source on existing air quality must be assessed. Air quality monitoring is one means of making this type of assessment. A monitoring network... 

A stationary monitoring network should yield the following information ... 

Figure 15-1 shows the Los Angeles, California, basin stationary air monitoring network, one of the most extensive in the United States (6). At most of these locations, automated instruments collect air quality data continuously. Five pollutant gases are monitored, and particulate matter filter samples are collected periodically. 

In addition to fulfilling the in-house requirements for quality control, state and local air monitoring networks which are collecting data for compliance purposes are required to have an external performance audit on an annual basis. Under this program, an independent organization supplies externally calibrated sources of air pollutant gases to be measured by the instrumentation undergoing audit. An audit report summarizes the performance of the instruments. If necessary, further action must be taken to eliminate any major discrepancies between the internal and external calibration results. 

Smith, D. G., and Egan, B. A., Design of monitoring networks to meet multiple criteria, in "Quality Assurance in Air Pollution Measurement" (E. D. Frederick, ed.). Air Pollution Control Association, Pittsburgh, 1979, pp. 139-150. 

List the reasons for establishing a stationary air monitoring network. 

EPA. Guidance for Using Continuous Monitors in PM-, Monitoring Networks. Research lii-angle Park, N.C. hrrp //www.epa.gov/ttnarntil/files/ambient/pm25/r-98-012.pdf. 

In Mexico City, several air quality parameters are measured continuously by an Automated Monitoring Network operated by the Under Secretariat of Ecology. Carbon monoxide, particulate matter, sulfur dioxide, nitrogen oxide, and ozone are the contaminants exceeding Air Quality Standards. Emissions produced by 2.7 million vehicles and 35,000 commercial and industrial outfits are not easily dispersed in a Valley located at 2240 m and surrounded by two mountain chains which hinder air circulation. An Integral Program, recently established to alleviate pollution, is briefly described. 

There is an additional Manual Monitoring Network, made up by 16 stations, committed to evaluate total particulate matter, PMIO (suspended particulate matter less than 10 /xm in diameter), sulfur dioxide and heavy... 

Global Environment Monitoring Systems (GENS) Air Monitoring Network... 

In designing a mercury monitoring network that includes a wildlife component, a principal objective would be to docrrment changes in merctrry exposure (and potentially effects) relative to changes in merctrry loadings to an ecosystem. More specific objectives might include the ability to ... 

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. 

Assuming limited resomces, the wildlife component of a mercmy monitoring network would likely have to rely on analyses of tissue from a small subset of candidate species identified earlier in this chapter, so identification of key species that both meet the criteria as good current indicators (see Section 5.5) as well as... 

Concerning indicator species, as a preliminary assessment in describing the wildlife component of a mercury monitoring network, based on criteria evaluated in Section 5.5 and studies cited herein, additional concerns noted above, and professional judgment of the authors, candidate wildlife species for inclusion in such a network have been selected and are indicated in Table 5.4. 

Candidate wildlife species for inclusion in a mercury monitoring network... 

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 ... 

It has applied or demonstrated new mathematical tools for optimizing pumping strategies and monitoring networks. 

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