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Disclaimer, Privacy and Security Notice

  1. This World Wide Web (WWW) site is provided as a public service by the Technology Innovation Program of the Environmental Protection Agency. It is operated under contract by Environmental Management Support, Inc.
  2. Information presented on this WWW site is considered public information and may be distributed or copied. The U.S. Government retains a nonexclusive, royalty-free license to publish or reproduce these documents, or allow others to do so, for U.S. Government purposes. These documents may be freely distributed and used for non-commercial, scientific, and educational purposes. Commercial use of the documents available from this server may be protected under U.S. and Foreign Copyright Laws. When individual documents on this server have different copyright conditions, it will be noted in thos documents.
  3. Links to Web sites outside the U.S. EPA Web site and non-EPA documents are for the convenience of the user. The Standards of Ethical Conduct do not permit the U.S. EPA to endorse any private sector Web site, product, or service. The U.S. EPA does not exercise any editorial control over the information you may find on these web sites and within these documents. These links are being provided consistent with the intended purpose of this Web site.
  4. When you come to this web site to browse, you do so anonymously. By default, EPA does not collect personally identifying information about you. We collect only summary information [see below] about the numbers of individuals who visit our web site and what those individuals look at. This computer system uses industry-standard software to create summary statistics, which are used for assessing what information is of most and least interest, determining technical design specifications, and identifying system performance or problem areas.
  5. The information above is also collected by Google Analytics on behalf of EPA. Google Analytics uses first-party persistent cookies, which the government classifies as Tier 2 persistent cookies. Tier 2 persistent cookies do not collect any personally identifiable information, but only those metrics listed above. In addition, persistent cookies can identify return visitors to by setting a small file in internet Web browsers. Unless you first opt-out (see below), the Google Analytics code used will automatically set a persistent cookie in the browser of the computer you are using to access

    Traffic statistics for are only reported to us anonymously and in the aggregate, and no information provided by Google Analytics is traceable to any specific individual. We use the information that we automatically collect to measure the number of visitors to the different areas of our sites, and to help us make our pages more useful to visitors. This includes analyzing Web traffic to determine the types of devices and browsers that view web pages most often and the level of demand for specific pages and topics of interest.

    You can opt-out by changing the cookie settings in your browser. See instructions on how to disable cookies in some of the most popular Web browsers. Google also provides an Opt-Out Browser Add-on for newer browsers. Opting-out will not prevent you from obtaining information from this website.

    For more information about the federal government's use of persistent cookies, please refer to the Office of Management and Budget's (OMB) Memo Guidance for the Online Use of Web Measurement and Customization Technologies (PDF).
  6. Where identifying information is asked of you (such as to respond to an information request) that information is provided voluntarily by you. It is used only for the stated purpose and is not made available for other purposes. By providing this information voluntarily, you are consenting to its collection for the stated purpose. See our notice of use and Privacy Impact Assessment (175KB/11pp/PDF) for more details.
  7. Unauthorized access to or unauthorized use of this website is subject to criminal, civil, administrative, or other lawful action. For site security and to ensure that this service remains available to all users, the U.S. Government may for any lawful government purpose, without notice, monitor, intercept, search, and seize any authorized or unauthorized communication to or from this website or information used or stored on this website at any time. Any communications or information used, transmitted, or stored on this website may be used or disclosed for any lawful government purpose, including but not limited to, administrative purposes, penetration testing, communication security monitoring, personnel misconduct measures, law enforcement, and counterintelligence inquiries.
  8. No additional attempts are made to identify individual users or their usage habits.
  9. For more information about the U.S. EPA privacy program and current contact information for the U.S. EPA Senior Agency Official for Privacy (SAOP), please refer to EPA's Implementation of the Privacy Act.
  10. If you have any questions or comments about the information presented here, or would like to view all personally identifiable information that is in your name and currently stored in support of this website for review and possible correction, please contact us through our Comments Page. You may also contact the EPA Privacy Hotline at 202-566-1668 or

Example of Information Collected for Statistical Purposes

Below is an example of the information collected based on a standard request for a World Wide Web document:

1999-06-08 10:32:39 - W3SVC5
GET /products/costperf/default.htm - 200 22927 5204 80 HTTP/1.0

1999-06-08 10:32:39
The date and time of the request. (or
The IP address (or host name) associated with the requestor (you as the visitor). Depending on the requestor's method of network connection, the IP address (or host name) may or may not identify a specific computer. Connections via many Internet Service Providers assign different IP addresses for each session, so the host name identifies only the ISP. The IP address (or host name) will identify a specific computer if that computer has a fixed IP address.

The site name designated internally by the server for logging purposes. It informs the server that this particular request came through a web site located on this server.

The location of the requested file.

The status code. 200 means the request was filled.

The size of the requested file in bytes.

The time required to complete the request in milliseconds.

80 HTTP/1.0
The port and protocol used to complete the request.

Identifies the type of browser software used to access the page, which indicates what design parameters to use in constructing the pages.

Identifies the operating system used to access the page, which indicates what design parameters to use in constructing the pages.

Identifies the session cookie being used by the server. This web site uses cookies to more accurately log both visits to the site and pages visitors view while on the web site. The use of cookies enables us to improve our site based on how users navigate the site, as well as the length of their visits. These cookies are automatically deleted at the end of your session.
Identifies the page which the user came from before visiting this page.

Requests for other types of documents use similar information. No other user-identifying information is collected.