GIS holds great potential as a tool for managing environmental site remediation data. While using GIS to locate Superfund sites is commonplace, GIS has played only a minor role in the review and analysis of chemical data gathered during an investigation or monitoring activity.
There are a number of reasons why GIS has not become commonplace in the evaluation of site remediation data. First, remediation projects generate huge volumes of data. Hard-copy Quality Assurance/Quality Control (QA/QC) reports can easily fill 10 or more boxes. Transferring data from paper to electronic format can be a daunting and costly task.
Second, GIS traditionally has not been used by remediation specialists during the decision making process. Typically the work of project managers, chemists, geologists, and risk assessors is brought together in static reports. A method for integrating these reports with GIS was not immediately apparent. Some participants in the remediation process were unfamiliar with GIS and related computer technologies.
In addition, objective measurements for pollution abatement have not been agreed on within the regulatory community. 'Bean-counts' and dollars spent on cleanups or containment have been the classic measure. While easily compiled, these data have not demonstrated a direct link to enhanced safety to people or the environment. Actually, this method of measuring progress has been a major source of friction between regulators and the regulated community.
Changes Favor Adoption of GIS
However, the regulatory climate has changed in ways that favor GIS implementation. Concerned over the need to quickly and accurately process an ever-growing volume of data, the agency changed data submission requirements. The NJDEP SRB now requires that all sites presently being remediated within New Jersey submit site data in electronic format. Recognizing the importance of GIS as a tool for visualizing site conditions and displaying and manipulating results, all location and chemical data submitted to NJDEP SRB are also now required to be GIS compatible. The move from hard copy to electronic data submission could accelerate the review and statistical manipulation of information, improving service to the regulated community and protection of the environment and public.
Using Digital Data
Some of the current and planned uses for the digital data generated under the new technical regulations include:
- Provide site-specific data analysis to case managers to aid them in routine tasks and decision making.
- Combine data from various sites to address problems on a regional basis and track down contaminant sources.
- Use the GIS as a repository for digital data on contouring soil and groundwater contamination, predictive modeling, and calculating contaminant risk exposures.
- Generate maps and other graphical outputs to communicate environmental risk issues to the public.
- Use GIS with environmental indicator analysis to track the effectiveness of remedial strategies over time for a particular site or region such as a watershed. Before these benefits can be realized, issues regarding the State-wide data collection need to be addressed. Issues to be considered include
- Cost-benefit analysis to determine whether the cost of converting from the present system to an electronic data submission system warrants the effort.
- Determine hardware and software requirements to accomplish data management goals.
- Create a standard, formatted electronic data deliverable and associated valid values for data submission.
- Communicate data format and quality concerns to the regulated community.
- Assess and describe the technical requirements associated with the effort.
- Train staff to administer the program.
- Develop or select a data management system that provides for quick and accurate data retrieval.
Developing the Program
Developing the human and computing systems to support NJDEP objectives posed the greatest obstacles to the project. A number of tools were incorporated into the data management process specifically to handle site remediation data. Both tools and systems will continue to evolve.
The HAZSITES data entry program, distributed by the NJDEP, facilitates manual entry of site data. The regulated community may submit data produced in other applications such as spreadsheet and database programs, or supplied by laboratory or contractor. Other software tools track data submissions, move data through the organization, and preserve meta-data associated with data deliverables.
Ensuring Data Quality
EQuIS for Windows, a product of EarthSoft, Inc., of Pensacola, Florida, was selected by the NJDEP as the environmental data management system for storing and accessing data. Through a set of procedures and import routines, data are evaluated against quality criteria. Passing data go to SRB staff while data failing quality checks are rejected and must be resubmitted. Once in the EQuIS system, large volumes of chemical data may be combined with other site-specific information such as geological and hydrological data.
Additionally, users may organize constituent groups, locations, and regulatory limits to support the analysis of data over a particular site or group of sites. For example, a project manager could group shallow monitoring wells to evaluate all volatile organic compounds above a particular cleanup level. This ability to aggregate data is critical to investigating site conditions.
While GIS is a powerful tool for evaluating site data, the cost/benefits of applying GIS may raise concerns without sound strategies addressing quality issues, implementing version control, and providing access to stored data.
Using the EquIS-ArcView GIS interface, managers can quickly and seamlessly retrieve data for a project or set of projects. Ancillary project information, such as location groupings and regulatory thresholds, are available through the interface if this information was incorporated in the data management system. The interface can connect to any project supported by EQuIS. Project data refresh each time the ArcView GIS interface is invoked. Accessing an updated common repository ensures that users are working with the same data as well as using the same conventions. Data evaluation can be performed using a custom graphic user interface (GUI) or through standard ArcView GIS functions.
Because this interface supports open system design, experienced programmers can easily develop their own ArcView GIS tools using the data tables that are provided within the interface.
The EQuIS environmental data management system addresses the problem of integrating analysis results from non-GIS tools. Data are stored in a common repository which is integrated with a variety of third party tools such as Surfer, Stratos, GMS, and LogPlot. Data generated using these tools can be combined within the ArcView GIS interface if these data contain coordinate information. From within the EQuIS-ArcView GIS interface, live data can be retrieved and compared using the tools that resource managers have long relied on for decision support.
Changing Performance Measurements
An interesting initiative using the data produced by the NJDEP involves both NJDEP and the United States Environmental Protection Agency (EPA), Region II. Encouraged by Environmental Council of the States (ECOS), NJDEP has joined in the National Environmental Performance Partnership System (NEPPS). This program focuses performance measurement on outcome-based measures of progress rather than activity-based measurements. The program emphasizes interpreting and communicating scientifically sound environmental information by using environmental indicators (EIs) to measure current conditions and trends over time.
This information will be used by departmental managers, the legislature, the environmental community, the regulated community, and the general public. Agency goals are being revised so they will be evaluated in terms of EIs. Accurate and reliable EIs that are understandable and communicable in nontechnical terms are vital for evaluating the progress of remediation activities.
Quantitative Environmental Indicators
The EPA Region II formed an Environmental Indicators Quality Action Team tasked with developing meaningful and accurate EIs. The team set up criteria for EIs that correlated the quality of the environment with the amount and distribution of contamination within the environment. This team developed a multimedia, mass balance approach for EIs called Quantitative Environmental Indicators (QEIs).
QEIs attempt to quantify factors that are not otherwise measurable such as the effectiveness of groundwater contamination extraction, amount of continuing sources or natural attenuation to groundwater, and identification of the contribution of unknown sources to groundwater. QEIs are defined by performing spatial operations that calculate the aerial extent of contamination, approximate the volume of contaminant, and derive the contaminant mass. QEIs provide insight into the dynamics of the system and relative contaminant distributions.
Classification Exemption Areas are defined as local areas of groundwater that do not meet water quality standards. The NJDEP SRB explored mapping the Classification Exemption Areas with GIS as a tool for calculating and visualizing QEIs. Case managers were contacted to arrange access to files. After reviewing these files, maps showing the aerial distribution of contamination were generated using direct digitizing. This approach proved tedious and sometimes did not produce a map. Graphic representations for QEIs were not feasible unless data were available in electronic format and could be manipulated through a GIS.
Providing Better Information on More Sites
Using the ArcView Spatial Analyst extension with the EQuIS-ArcView GIS interface, staff scientists are able to quickly interpolate chemical concentrations. Data are assessed in terms of area and volume using depth information. Using the same techniques that were applied manually to quantify contaminant mass, numbers are derived for each of the environmental indicators through the ArcView GIS system. Instead of evaluating QEIs for one or two sites, NJDEP can assess 10 to 20 sites by using GIS to automate the task.
Through this program of environmental data collection and standardization utilizing GIS, the NJDEP is creating the framework for a system that provides the regulatory community with his information to make better decisions, communicate the status of environmental conditions, and improve service to the residents of New Jersey.