|
Reviving the old data: The spatial environmental database development approach
These two agencies are also responsible for issuance of permits for the various activities of the oil and gas companies. This issue of permitting processes is the most significant control that these agencies exercise on the companies. For example, an environmental permit is required before a company can drill any oil well. The application for the permit is often accompanied by a report type. Different types of reports are required for different oil and gas activities and at different stages of their operations. Some of the known environmental reports include Environmental Impact Assessments (EIA), Environmental Baseline Studies (EBS), Environmental Evaluation Report (EER) and Environmental Monitoring Plan (EMP) etc.
Environmental data collection is intensive as both primary and secondary data collection approaches are always employed. The methodologies of data acquisition and analysis have been well standardised in the country. The resulting reports from any environmental studies are often data intensive as they often consist of information about virtually all aspects of environment ranging from vegetation, wildlife, soil, water, underground water etc depending on the focus of the study. It is common therefore to find that similar reports have almost similar data. Most of the reports also contain raw field data and also the synthesized data. This is to allow for further verification of the data contained in the reports. Project Justification There are two major limitations to most of these reports especially those reports that predate 1995. The first limitation is that majority of them are in analog format. The problem is due to the low computer knowledge and high cost of hardware and software acquisition in the country prior to 1995. Hence, many of the reports are not computerised, therefore making storage of the data in digital format difficult. Secondly, many of them lack good georeferencing quality. In other words, the coordinate locations where field sample data were collected were not recorded in the reports. The absence of coordinate locations in most of the report may be due to low level of Global Positioning Systems (GPS) usage among most of the environmental companies for environmental data acquisition prior to 1995. This makes it difficult to reference almost all the data contained in most of the reports to their true geographical locations in space. The best that can be achieved might be to reference the entire data in a particular report to the facilities from where they were measured or to a particular oil field etc. However since science emphasises repetitiveness, it should be possible to go back to those precise positions (if the coordinates locations are known) and collect similar data at some time in the future. The need to monitor, model and map environment over a long period of time has occasioned the need to have data acquired in a time series manner and in digital format (NDES 1997). To have data in time series then means that those pre 1995 data have to be converted to digital format and coordinates will have to be provided for the locations without any coordinates, before they are integrated into any available digital environmental database. Secondly, since precision in environmental data collection analysis and reporting is the focus in most of the environmental departments in many of the oil and gas companies, those pre 1995 data have to be georeferenced to their true locations in space. One advantage of this holistic approach to environmental data management is that it ensures that all environmental data are stored together. This would reduce or totally remove duplication by the oil company in data collection except when it is necessary as they can readily plot all their available environmental data within one single environment. |