Mapping the Environment on the Web


by / July 31, 1997
If a picture is worth a thousand words, the Environmental Protection Agency (EPA) has provided the ability to talk up a storm. By making a series of geographic information system (GIS) mapping applications available over the Internet, the EPA is allowing government agencies and citizens to look at information such as air and water pollution sources in new ways. Instead of looking at pages of text, users can now map complex GIS information for any geographical area in the United States from their desktop computers.

This new mapping capability is useful for local governments that don't have the budgets to implement mapping technology, and for state regulatory staffs who may use the information to help set priorities for their permits and inspections. It also helps community and environmental justice groups as they research facilities that might be impacting watersheds and other natural resources.

The EPA has made this possible by combining its Web-enabled Envirofacts facility data warehouse -- an Oracle relational database of EPA-regulated facilities -- with an ArcInfo GIS database containing national spatial data. This combination of data systems -- called Maps on Demand (MOD) -- gives users a powerful Web-based tool to map and access air pollution levels, water-discharge permit compliance reports, Superfund clean-up decisions, and trends of toxic chemical releases and hazardous waste handlers, using site maps and text reports.

MOD helps users better understand regulatory information by showing them EPA-regulated facilities in relation to surrounding geographic features. By making GIS mapping available over the Internet, users have a more accurate, less expensive way to map information on their own. In the past, EPA staff had to research records manually to fulfill a request for information, which was slow and expensive.

Envirofacts is an application within the EPA's main Web site . Its purpose is to make all EPA information subject to the Freedom of Information Act -- including regulatory, spatial and demographic data -- accessible to federal, state and local regulators, citizens, and private industry. The general public and the EPA's 17,000 employees use Envirofacts to access information such as hazardous waste, air and water emissions, and toxic releases. The site receives more than 200,000 hits a month from the Web and thousands more from those using database access software.

Through the Envirofacts database, users generate queries by entering a specific facility name, ZIP code, city, county or state into an online form. The query generates a list of facilities that match the criteria. Users select a facility to receive a detailed environmental profile with information such as the toxic chemicals released over the last year, and air emission estimates for pollutants regulated under the Clean Air Act. Regulators can use this information to monitor noncompliant companies by regularly checking permit status, and to ensure compliance to permit limits. The public can use the information to better understand how a facility is regulated and what a facility discharges in a community.

Envirofacts uses custom software to extract data from EPA's five national mainframe systems. The software pulls information into the Oracle Envirofacts database, which is updated monthly by the agency. The Oracle7-based data warehouse is currently 40GB and contains 2,400 pages of metadata information describing how information in the warehouse is structured.

The data warehouse includes regulatory information on more than 700,000 facilities over the past five to eight years. The Envirofacts database will grow to hold over a terabyte of information as the agency adds up to three more national databases -- drinking water, hazardous waste and water treatment project information -- to the data warehouse this year, and configures its spatial data holdings into the warehouse data management system.

When Envirofacts went live in March 1995, the EPA rolled out a Web-based interface and desktop tools to its regional offices so staff could access the online data.
Because employees can tap into all the information they need through an Internet connection, they no longer have to remember multiple account numbers to access different databases on the agency's mainframe, or wait several days for IS to create reports they need. Like the public, they simply log onto the Internet and point and click to access information.

Mapping In Envirofacts
The Internet provides the EPA with a strategic platform more conducive to government's shrinking budgets -- it is less resource-intensive and expensive to produce and maintain than the traditional GIS mapping methods. And more than 6,000 users download 1.8GB of information from the MOD site each month.

MOD links EPA's data warehouse to a GIS ArcInfo database that runs on a Digital Alpha platform. The data is stored in a Clariion RAID array which holds 60GB of spatial data online. Previously, anyone wanting to map GIS information could either pay for EPA-generated maps, deploy a costly GIS workstation with an ArcInfo database and hire a specialist to run it, or rely on static CD-ROMs.

With MOD, non-technical users can access the agency's most complete and accurate information resources and mapping capabilities by simply pointing and clicking on a graphical interface. This mapping capability is an important step forward -- instead of struggling with tabular information, users now have well-organized, easy-to-use mapping tools that let them dig into different layers of information.

MOD creates maps that include environmental information and nationally consistent spatial data. Within MOD, a SiteInfo application enables users to create maps and text reports of EPA-regulated facilities by entering a facility's latitude and longitude. If users don't know these coordinates, the Envirofacts query form can pull them up using the facility's name and geographic information.

Another MOD application called BasinInfo allows users to map watersheds using U.S. Geological Survey hydrologic unit code data. By selecting a region and criteria, such as program system and demographic information, users can map a watershed and see the facilities in and around the watershed.

For example, if a group of water specialists wants to assess what is impacting a water basin in a certain geographical area, they can enter the location they want to look at, and the application will generate a map of the area that also shows EPA-regulated facilities within the area or boundary. They can go further into the Envirofacts data warehouse and submit queries on the facilities to see what regulatory programs these facilities have reported under and check if they comply with permit limits and what chemicals they are discharging. A Chemical Reference feature obtains information on the chemicals' effects on the environment and public health.

The Facility Density Mapper gives users a big-picture view of the number of facilities in a geographic area. While SiteInfo and BasinInfo maps plot program records, which show whether a facility is a Superfund site or water discharger, for example, the Density Mapper plots the actual number of facilities to a given location. This enables users to pick out the high density areas of EPA-regulated facilities. Then they can go to Envirofacts to do a more in-depth analysis on the facilities.

The Mod Future
In the future, the Envirofacts team will add links to all three mapping applications. That will enable users to click on a program record or facility on the map and pull up detailed information directly from the Envirofacts data warehouse without having to manually submit a query. For example, a parent concerned about a facility next to their child's school will be able to drill down on the map to see what the facility produces, why it is being regulated by the EPA, etc.

The EPA also plans to enhance its MOD application with realtime mapping to make GIS mapping even easier and more thorough.

Envirofacts' future is wide open to additional capabilities. With the Internet as the EPA's strategic platform, the agency can continue enhancing Envirofacts to make more information -- and the tools needed to easily access and analyze it -- available to a growing user community.

Pat Garvey is Envirofacts manager, Enterprise Information Management Division for the Environmental Protection Agency.

August Table of Contents