The Maine Department of Environmental Protection-Geographic Information Systems Unit (MDEP-GIS Unit) is currently developing a multifaceted Geographic Environmental Management System (GEMS) using ArcView Version 2 and ArcInfo. As an ArcView Version 2 developer site, the MDEP-GIS Unit had an early start in developing the Maine Oil Spill Information System (MOSIS) for contingency planning, response, and cleanup. This system is composed of a series of modules within the GEMS framework. The ArcView Version 2 object-oriented architecture allows multiple modules of GEMS to be developed by sharing tools common to each. An earlier version of the Oil Spill System was developed using the ArcInfo ARC Macro Language (AML). It has since been conceptually redesigned in order to better utilize the intuitive graphical user interface and object-oriented scripting language of ArcView Version 2.
ArcView Version 2 also enables MOSIS to be used on networked personal computers (PCs), allowing greater portability and access for end users. After the new conceptual design was finished, prototyping began on MOSIS using ArcView Version 2 beta. The first module to be developed is called the Map Atlas Production System (MAPS). Its main function is to enable novice GIS users to print or plot predefined map atlases, at a selected geographic location, a chosen geographic extent, and a consistent scale. Much of the functionality of this module is implemented using the ArcView Version 2 Avenue scripting language, while the remainder was completed using other tools. Some of the tools identified that have been, or may be, necessary to create the envisioned GEMS are a graphics package, Corel Draw, for developing symbology; a user interface resource builder, Neuron Data System's Open Interface, for developing user interface resource files such as custom dialogs; databases, ORACLE and FoxPro, for storing the large amounts of attribute data needed to complete the system; and ArcInfo for more advanced geoprocessing tasks.
While working on MAPS and the beginnings of the oil spill specific functionalities of MOSIS, it was realized a commonly shared framework for all applications was needed. Thus, the application framework was created as the foundation on which all MDEP-GIS Unit GEMS applications are built. The application framework handles the internal workings of all GEMS applications such as user levels; saving user-defined attribute objects, documents, and projects; and setting system and user defaults. With the application framework in place, MAPS was redesigned using its architecture.
The next GEMS module to be developed was the data catalog. The data catalog meets the increasingly important role of creating, updating, and storing metadata with each geographic data set. It provides the end users with a means of storing information about where geographic data are located on disk, and what standard symbolization is used for that data. It also allows the end user to search or browse for geographic data sets with a limited amount of information, such as the geographic area and type of data needed. Three types of reports can be created from the results of a search. MOSIS, which addresses the oil spill planning and response specific functionalities, was then redesigned using the application framework. It includes tools for oil spill source location and plume tracking, contamination reports, resources-at-risk reports, and response logistics reports. Note that MOSIS contains all of the oil spill specific functionality within GEMS and that the other two modules, MAPS and the data catalog, are general enough to be used for many other environmental management applications.
The paper will focus on the current state of GEMS, the steps it took to get to that point including the problems and discoveries made along the way, and the future of GEMS, as well as other GEMS modules the MDEP-GIS Unit will develop using the knowledge and techniques gained by this experience.
David W. Pollock
Maine Department of Environmental Protection
Geographic Information Systems Unit
State House Station 17
Augusta, ME 04333-0017
Telephone: 207-287-6166
Fax: 207-287-7826
Email: eidpoll@gatekeeper.ddp.state.me.us
James Richards
Khaled Hassen
Christopher Kroot