The U.S. Environmental Protection Agency (EPA) maintains an extensive web site providing resources for both scientists and the general public. The EPA, like many governmental agencies, can be found by entering: www.agency.gov, substituting the name or abbreviation of the agency. Thus, a likely place to find the EPA would be www.epa.gov ^*. Note that the full address is http://www.epa.gov, but you may not need to type in the http://.

Go to the EPA web site and explore it for a few minutes. Periodically use your back button (or Go button) in order to keep track of where you are. If you get lost, start again at the EPA's home page. As you browse, you may come across EPA's Office of Air and Radiation (OAR) that contains a number of "consumer-friendly" documents.

The EPA offers many useful documents on air quality. Find one, and provide the following information:

• Name of the EPA document
• URL
• Summary of information provided
• Last updated (if provided)
• Notable features (good or bad)
• Something interesting that you learned

^*You also can use the search button on your browser to locate the EPA.

Table 1.2 in your text lists peak ozone levels in 12 U.S. cities. As you can see from the table, ozone is the pollutant that most often exceeds the air quality standards set by the EPA. What are the current ozone levels in these cities? To answer this question, use the AIRNOW ozone maps provided by the EPA.

Estimate the ozone levels for one of the cities listed in Table 1.2. First select a state or region, and then chose the option under the map, "Yesterday's peak values (1 hour)" and finally click to display the map. Do your best to estimate the location of the city you select (it may not be shown on the map) and use the color codes provided to estimate ozone level. Compare what you find using AIRNOW with the value listed in Table 1.2. What factors might be contributing to any differences you observe?

Periodic tables are available on the web that list the properties of elements, their date of discovery, their naturally occurring isotopes – and much more. Thus, the web can give you quick access to information that it might take you hours to find using reference books.

Use a search engine to bring up a list of periodic tables. Go to one of these periodic tables to find out more about an element of your choice. You probably will obtain more complete information if you select an element with atomic number of 94 (plutonium) or less.

Find out what year your element was discovered, whether it is a solid, liquid or gas, its appearance, where it is found, and any other two facts, such as toxicity, cost, uses, etc.

Following the directions given by your instructor, get together with other students in your class to answer questions such as: Are most elements gases, solids or liquids? Which elements were discovered first? Last? Are most elements found "free" in nature, that is, not combined with any other elements? Do the elements chosen combine with other elements to form compounds?

Go to the EPA web site and find the Toxic Release Inventory (TRI) for your state and for your locale. a. Compare the current level of toxic emissions with what they were a year or two ago. b. Which emissions (if any) have decreased and which have remained the same or increased? Determine, if you can, a reason for the changes.

Note: Check the 1998 TRI State Fact Sheets (scroll down), 1997 TRI State Fact Sheets and the 1996 TRI State Fact Sheets You will need Adobe Acrobat reader to view the documents for each state (two pages each). Scroll down past the lengthy introductory material to find the states listed alphabetically.

As a public service, local and national agencies provide useful documents on the web about radon. You can bring up a list using one of the search engines available on the web. In order to find public service documents specifically relating to radon in homes, you may want to add terms such as "detection", "air quality" or "EPA" to your search string.

a. Find two web sites on radon provided by public agencies. For each, list the title, the source, and the URL.

b. How can you measure the radon levels in your home? Search the web for a company that sells radon test kits. Describe the kit, including its price. If you don't find anything at first, switch to another search engine.

c. Is the information about radon from commercial sites any different in its objectivity from that provided by agencies as a public service? If so, discuss the differences and reasons for them.